Hashem tested Avraham in order to evaluate the extent of his faith. Before the trial, Hashem did not know whether or not Avraham would be willing to sacrifice his son for God.
Meaning of "נִסָּה" – Ralbag understands the word to mean "test", a procedure established for purposes of evaluation. Hashem was testing Avraham so as to discern his level of awe and obedience.
Hashem's knowledge – According to Ralbag, Hashem's knowledge is not complete. While He knows all the choices open to a person, He does not know which path the individual will choose to follow.1 As such, He did not know in advance whether or not Avraham would acquiesce to sacrifice his child upon Hashem's demand.2
"עַתָּה יָדַעְתִּי כִּי יְרֵא אֱלֹהִים אַתָּה" – Ralbag is able to explain this verse according to its simple sense; only "now," after the trial, did Hashem know with certainty how God-fearing Avraham was.3
The test – Ralbag asserts that Hashem intentionally worded His demand ambiguously4 so that it could be understood in one of two ways: Avraham was to sacrifice Yitzchak as an Olah offering, or Avraham was to take Yitzchak in order to sacrifice an Olah.5 Since the second reading is one which a person would only understand if they found the first possibility objectionable, Hashem wanted to see if Avraham was so willing to abide by Hashem's word that he would not even seek out the alternative reading.6
Avraham's feelings – Ralbag presents an Avraham whose love for Hashem and desire to obey Him was so strong that all else paled in comparison, enabling him to go with ease even to sacrifice a beloved son.7 Avraham's eagerness to comply with Hashem's words is demonstrated by his early rising to do God's bidding and lack of questioning of the command.8 Ralbag further claims that the fact that Avraham achieved prophecy while awake proves that even in the moment of the actual slaughter he was neither worried nor sad about the act.9
"אֱלֹהִים יִרְאֶה לּוֹ הַשֶּׂה לְעֹלָה בְּנִי" – Ralbag maintains that these words of Avraham constitute a prayer10 that Hashem's command to him actually turn out to mean11 that a sheep (and not YItzchak) would be the Olah. Ralbag, thus, suggests Avraham recognized that there was a second way to comprehend Hashem's words, but that, nonetheless, he was unwilling to act upon it without a direct clarification by Hashem.
How can Hashem command murder? According to Ralbag, Hashem had never intended for Avraham to actually sacrifice Yitzchak,12 which is why He worded the command in a way which allowed for the second (and ultimately correct) possibility that Yitzchak was brought to the mountain only to witness an Olah offering. As such, Hashem had never commanded an immoral act. Ralbag's reconstruction is nonetheless difficult since if Hashem intended that Avraham understand that he was to sacrifice his child (as Ralbag maintains), then the morality of the command (and Avraham's ready agreement) is still in question.
Can Hashem change His word? According to Ralbag Hashem never changed His mind, nor went back on His word. From the beginning it was neither His intention, nor His command to sacrifice Yitzchak.
For Avraham
Avraham, rather than Hashem, was supposed to learn something new from the experience. This position subdivides regarding whether it views the test as beneficial or punitive in nature:
Means to Benefit Avraham
Acting on Hashem's directives brought Avraham to new levels of faith, and merited him rewards that he would never have received had Hashem not tested him.
Meaning of "נִסָּה" – These commentators split in how they understand the word:
Test – Both R. Saadia and Ramban explain that the word "נִסָּה" means tested, but suggest that a test need not be for the tester. It is the person being tested who gains from the experience. [Hashem, in contrast, knew all along what was to happen.]
Accustom – According to R"Y Albo and the Biur, on the other hand, the root "נסה" means to habituate.15 By commanding Avraham to sacrifice his son, Hashem trained his heart towards proper fear and service of God.
Hashem' knowledge – As these sources agree that Hashem gained no new knowledge from the test, the verses pose no theological issue regarding Hashem's omniscience and fore-knowledge.
What did Avraham gain from the trial? Most of these sources assert that the point of the experience was for Avraham to actualize his potential, changing his thoughts into actions.16 This accomplished two things:
Self-development: R"Y Albo and the Biur explain that acting on a belief serves to strengthen that belief.17 Though Avraham's willingness to do Hashem's bidding and sacrifice his son was not in question, having to actively bind Yitzchak and raise the knife brought his fear of God to new levels. Undergoing a trial changes a person in a way that merely thinking can never do.18
Increase reward: Ramban and R"Y Albo19 maintain that after the trial, Avraham could receive a reward not only for his good intentions, but also for his positive actions. R. Saadia points out that Hashem often gives the righteous many trials on earth so as to merit them redoubled reward later.20
"וַיְהִי אַחַר הַדְּבָרִים הָאֵלֶּה" – According to R. Saadia the "things" mentioned refer to the previous trials that Avraham had undergone. He21 claims that Hashem only tests a person who has proven that he will not fail.22 As such, the increased trials can serve only to reward.
Avraham's feelings en route – Rav Soloveichik23 portrays an Avraham who is filled with dread and suffering while en route to fulfill Hashem's command. It was this suffering, he claims, which was crucial for Avraham's growth. If he was to strengthen his connection to Hashem, Avraham need to feel the anguish of self-sacrifice .24
"עַתָּה יָדַעְתִּי כִּי יְרֵא אֱלֹהִים אַתָּה" – These sources differ in how they understand the verse:
Made known / was known – Rav Saadia suggests that the word "יָדַעְתִּי" should read as if written, "והודעתי".25 Through the akeidah Hashem announced to the world the level of Avraham's righteousness. Ramban similarly rereads the verb "יָדַעְתִּי", but turns it into the passive, "נודעה". Now that Avraham actualized his potential, his awe of God was known in practice.
Speech of angel – Seforno, instead, claims that it is the angel speaking in his own name who declares, "now I know that you are more God-fearing [than me, the angel]."26
How can Hashem command murder?
Can Hashem change His word? Ibn Ezra asserts that this is not the only place where Hashem appears to have changed His mind, pointing to the replacement of the first-borns with the Levites as another example. Nonetheless, he explains that in this story, the fact that the narrative opens with the words "And Hashem tested Avraham" proves that from the very beginning Hashem had no intention of Avraham's carrying through with the slaughter. R. Saadia adds that precisely because this was a test, Hashem had to allow Avraham to think He meant one thing when He intended another and therefore could not have explicitly revealed his true intentions.27
Means to Punish Avraham
The experience was meant to punish Avraham for having made a covenant with the Philistines.
"וַיְהִי אַחַר הַדְּבָרִים הָאֵלֶּה" – Rashbam maintains that these words serve to connect our unit with the immediately preceding one, and are Tanakh's way of linking the two stories.28 The opening, thus, suggests that Avraham's making of a treaty with Avimelekh is what prompted the command to sacrifice Yitzchak.29 Hashem was upset that Avraham made peace with the Philistines since their land was included in His promise to Avraham, and thus the prohibition "לֹא תְחַיֶּה כׇּל נְשָׁמָה" applied to them as well.
Meaning of "נִסָּה" – According to Rashbam, the word "נִסָּה" in our verse means to distress or provoke rather than to test.30 Since Avraham's interactions with the Philistines went against Hashem's will, Hashem punished Avraham by commanding that he sacrifice his son. Rashbam presents the trial in measure for measure terms, having Hashem say: "You were proud of your son, making a pact between him and Avimelekh's descendants, now go and sacrifice him, and see what is to become of such a treaty!"31
Hashem's knowledge – Since Rashbam does not understand the story as a test at all, he eliminates the question of why Hashem, in his omniscience, would need to test someone in order to know how they will act.
Avraham rewarded – The fact that Avraham is rewarded and deemed to be "'God-fearing" at the end of the experience is hard to reconcile with the view that the whole ordeal was a punishment. However, It is possible to suggest that the akeidah served not only to punish Avraham but also as an opportunity to correct his mistakes.32 If the pact with Avimelekh demonstrated a lack of obedience to Hashem's will, Avraham's utter submission during the akeidah proved that he was once again God-fearing and, as such, deserving of reward.33
Rashbam understands the verse to mean that after the event, Avraham's fear of God became public knowledge, apparent to the entire world.34 It was not Hashem who gained new knowledge, but rather the public.
Alternatively, Hashem might be speaking of His own knowledge. Earlier, in his interactions with the Philistines, Avraham had not acted in a God-fearing manner, but now, once again Hashem can recognize Avraham's obedience. This is not theologically difficult, since according to this reading Hashem did not lack knowledge which was then supplied, but rather Avraham lacked fear which he then achieved.
How can Hashem command murder?
Polemical motivations – It is possible that Rashbam's interpretation is at least partially polemically motivated:
Since Christians view the story as a prefiguration of Jesus's death on the cross, Rashbam might have wanted to cast the story in a much more negative light, suggesting that it describes not the epitome of Avraham's relationship with Hashem, but a punishment.
Y. Bin-Nun35 alternatively suggests that Rashbam might be combating the idealization of the akeidah common among those in the Middle Ages who were forced to martyr their children for God, and looked to Avraham's action as a model to emulate.36
For Others
The trial was intended for outsiders so that they appreciate both Hashem's choice of Avraham, and understand what is the correct and desired service of Hashem:
Demonstration of Avraham's Worthiness
The akeidah was meant to demonstrate Avraham's worthiness and why he merited to be chosen by Hashem.
Test – Most of these sources understand the word according to its simple sense, to mean "to test" or "try" but claim that a test is sometimes aimed not at the tester, or even at the one tested, but rather at the audience who watches or hears of the trial.38
Raise as a banner – Bereshit Rabbah, Abarbanel and Keli Yekar39 assert that the word "נִסָּה" is related to the word "נס", or banner. Through the akeidah, Hashem set up Avraham as a sign for others to emulate.
Hashem's knowledge – This approach can maintain Hashem's perfect knowledge since it does not assume that He learned anything new from the experience.
For whom? Ibn Ezra questions this whole approach on the grounds that no one but Avraham and Yitzchak were present at the event. As such, how could these sources claim that it was intended for others?
Satan and other angels – Jubilees, Pseudo-Philo, Bavli, Bereshit Rabbah, Rashi, and R"Y Bekhor Shor suggest that the test was aimed at the Satan and/or other angels who had questioned Avraham's loyalty and obedience to Hashem.40 [Such beings need not have been physically present to see the event.]
Israel and other nations – The other sources more simply suggest that the lesson was for those living in or after Avraham's generation who had heard of (even if they did not witness) the event. Radak points out that word of the experience spread due to its being recounted in the Torah.41
What were people supposed to learn? All these sources agree that the akeidah was supposed to demonstrate Avraham's worthiness, but disagree regarding the specific message it was supposed to impart:
Avraham's unique fear and obedience – Most of these sources claim that the trial was meant to prove to all the extent of Avraham's love of and obedience to God. Avraham's willingness to sacrifice his only, beloved child at Hashem's behest, proved why Avraham merited to be Hashem's choice.
Avraham worthy despite not practicing child sacrifice – Shadal suggests that through the akeidah Hashem wanted to teach both Israel and other nations of the time that the fact that His followers do not practice child sacrifice is not a sign of lack of devotion to God. Avraham's readiness to sacrifice Yitzchak proved his love of God and demonstrated that had Hashem asked for it, Israelites, too, would be willing to give up their loved ones. Hashem, though, has no desire for child offerings.42
What made Avraham's sacrifice so special? Shadal's position raises an important question: If many people in Avraham's day practiced child sacrifice, why did Avraham's actions prove him more worthy than others?
Avraham not unique – For Shadal himself this is not a question, as he does not suggest that the story's goal is to show Avraham's uniqueness, but only that he is no less devoted than others.
No ulterior motive – Philo On AbrahamAbout Philoasserts that most people who offer their children in sacrifice do so with an ulterior motive in mind, either from a desire for glory or out of fear and the hopes of preventing some catastrophe.43 Avraham, though, had neither purpose in mind, and only the desire to do Hashem's bidding. Moreover, Avraham was not offering any child, but his beloved, only child,44 which had been granted to him miraculously in his old age.45
Full awareness – Rambam adds that the fact that Avraham first bound Yitzchak three days after receiving the Divine directive means that he was not acting in a state of shock or bewilderment in which he could not think through the action's consequences, but rather with full cognizance of the meaning of the deed. He acted out of neither desire for reward nor fear of punishment, but solely out of love and awe.
Dissonance with prior value system – Alternatively, the difficulty of the test for Avraham was precisely because he had grown away from pagan norms and had a different understanding of both God and what that God stood for.46 To heed Hashem's word, he had to struggle with a value system which called child sacrifice "murder". He had to question how a loving, moral God (who had instilled in Avraham the importance of "צְדָקָה וּמִשְׁפָּט") could simultaneously issue such a directive. Finally he had to question whether or not Hashem kept His promises and what was to become of the promise, "כִּי בְיִצְחָק יִקָּרֵא לְךָ זָרַע".
"וַיְהִי אַחַר הַדְּבָרִים הָאֵלֶּה"
According to the Bavli47 the verse is referring to events not written in the Torah, which led to the need to demonstrate Avraham's righteousness to the world. R. Yochanan suggests that the phrase refers to the complaints of the Satan against Avraham,48 while R. Levi suggests they refers to Yishamel's claims that he was more worthy than Yitzchak.49
Alternatively this approach could say that the phrase serves to link the akeidah to the previous chapter's description of the miraculous birth of Yitzchak and the promise "כִּי בְיִצְחָק יִקָּרֵא לְךָ זָרַע", both of which contributed to the difficulty of the trial.
Feelings en route – Rambam suggests that the three day trek gave Avraham time to consider all teh ramifications of Hashem's command and
How can Hashem command murder? Midrash has Avraham grappling with this question.
Prohibition of child-sacrifice – The experience of the akeidah was meant to proclaim Hashem's rejection of child sacrifice.
Truth of prophecy – Rambam further asserts that the story teaches that prophets have no doubts at all as to the veracity of their prophecies. Avraham knew with certainty that it was Hashem speaking to him, or he would never have done the deed.
Priority of Divine will over human ethics – Many moderns scholars suggest that the point of the akeidah was to teach that when human ethics seem to conflict with the Divine will, priority must be given to Hashem's command. This is either because true morality is only defined by Hashem's word 50(and as such, Hashem can command that one give up their concept of morality),51 or because one must have faith that, despite appearances, Hashem's command is of necessity moral.