A test is only a test if there is a possibility of passing it. That is why Avraham was tested with the akeidah and not Sarah. In fact, the midrash tells us that she died just hearing about it (the harsher version is that she thought he was actually killed, the milder version that she knew that it only almost happened).
A possible reason why Avraham could be tested about this and not Sarah is the difference between a mother’s love for her child and a father’s. But that doesn’t necessarily mean that Sarah loved Yitzchak more than Avraham. Some fascinating wording in the Torah may actually indicate otherwise.
One does not need to be an expert in Rashi to understand why he comments on the phrase, “take your son, your only one, whom you love, Yitzchak” (Genesis 22:2). We join him in wondering, why not just say, “Yitzchak?” (It is incidentally enough of an issue to have prompted Muslims to claim that Jews added the word, Yitzchak; and that the phrase, only son, must be referring to the first son, Yishmael.) In fact – as Rashi inidcates – each word is pregnant with meaning and addresses a different aspect of Avraham’s attachment to Yitzchak. Hence each word presents a different aspect of God’s test of Avraham.
Given the strength of the question and the poignancy of the answer, it seems strange that so few commentators even notice the truncation of this phrase later in the story – twice. (My theory is that by the time we reach the story’s climax, we are all too exhausted to still be looking for questions!) Yet sure enough Avraham is only praised for not withholding his son, his only one in verse 12 and then again in verse 16. What happened to, “whom you love, Yitzchak?”
If I am indeed correct that each of the four descriptions of Yitzchak represents a different aspect of the test and Avraham is only congratulated for two, could it not be that Avraham did not pass the two aspects of the test that went unmentioned? This is not to take anything away from Avraham. In this particular test, 50% could easily be considered a high mark. Moreover, God also congratulates Avraham, even if the suggestion is that he could have done more.
Perhaps we can understand this as follows: The sacrifice of Yitzchak was never meant to be primarily physical, but rather mostly emotional. In the four words with which God describes Yitzchak, it appears that Avraham was to rid himself of any attachment he had to his preeminent son. The command to destroy him was to be total. The only consolation available was the trust that God somehow knew best what was correct.
In some aspects, Avraham passed the test. He was apparently able to destroy his parental connection to Yitzchak = your son, and his connection to him as the special son = your only son, meaning the one who would define his progeny. But it appears that he could not get rid of his love for him, nor for his appreciation of Yitzchak’s unique personality and talents. None of this, of course, would have prevented him from going through with the sacrifice. But, as mentioned, that was not the main issue.
On some level, Avraham’s failures were a litmus test of what was so closely tied to his essence that he was simply ineffectual at trying to get rid of it: His love was not something he could easily control – it was a way of looking at God’s creatures in general, and at those who did His will in particular. Perhaps his were the feelings echoed by Rav Kook so many centuries later: It is impossible not to be filled with love for every creature, since the light of God shines in everything (emphasis added, Midot HaRayah, Love 1:3).
Avraham also failed at eliminating his attachment to the uniqueness of Yitzchak. If Yitzchak was already thirty-seven – as is traditionally understood – he must have already been a spiritual giant the likes of which there was none to compare. Independent of any familial relationship, Avarham could not help but be totally engrossed in this wonderful religious personality.
Given the loftiness of the connections that Avraham could not sever from Yitzchak, it is not impossible that God was ultimately pleased with Avraham’s failures. If so, it would parallel His apparent pleasure with Moshe’s inability to overcome his humility when commanded to do so (see my Moshe’s Stutter: The Pardonable Sin). True, the ideal is always to listen to God. But when the impediment is an outstanding personality trait, God seems understandably more prepared to let it go. May we experience the failures of the fathers, more than the successes of the children!