Rabbi Huna said in the name of Rabbi Eliezer the son of Rabbi Yosei HaGelili: The Holy One of Blessing first places the righteous in doubt and suspense, and then reveals to them the real meaning of the matter, as it is written “to the land that I will show you (Gen. 12:1); “On one of the mountains which I will tell you”; “And make to it the proclamation that I bid you (Jonah 3:2); similarly, “Arise, go out into the plain and I will there speak with you (Ezek. 3:22).
~ Bereishis Rabbah 55:7-8.
About what could a person as spiritually mighty as Avrohom Avinu harbor doubt?
It is inconceivable that Avrohom Avinu should have doubted G-d’s oft-reiterated promise of issue through Yitzchok “more numerous than the stars of the sky and the sands of the seashore.”
It is equally inconceivable that Avrohom Avinu should have thought G-d really desired the death of Yitzchok, his “child of promise.” Avrohom was, after all, no dummy. He could parse a sentence as well as the next guy, and clearly, G-d never actually commanded him to schecht Yitzchok. G-d merely says, “bring him up there as an offering.”
So, in my fertile imagination, Avrohom’s inner dialogue during his three day sojourn to Mt Moriah may have gone something like this:
“I know that G-d is G-d, and that when G-d commands, man must obey. But G-d would never countenance human sacrifice, which is anathema to Him. Nor would G-d be proven a Liar – heaven forbid! – by neglecting to fulfill his promise to Me!”
At this point, perhaps only in my imagination, Avrohom may have broken out into a cold sweat. What if I am wrong? he might have wondered. G-d would not command me to do something that is evil. What if this is not G-d speaking to me at all? What if I am deluded? What if my whole life is a LIE? Says Midrash Tanchuma:
“As Avrohom and Yitzchok walked toward Mount Moriah, S*tan joined them on the road, appearing to Avrohom in the guise of an old man. Said he to Avrohom, ‘where are you going?’ Replied Avrohom, ‘to pray.’ Said S*tan, ‘Since when does a person go to pray with fire and a slaughtering knife?’ Said Avrohom, ‘We may tarry for a day or two, this is so we can slaughter and roast and eat.’ Said S*tan, you old fool! It was not G-d, but I, who spoke to you, saying, “Please take your son…’ And now you’re going to destroy the child that was given to you in your hundredth year.’ Said Avrohom, ‘It was not S*tan, but G-d Himself who commanded me. I shall pay no heed to you.’
“So S*tan departed from Avrohom and appeared at Yitzchok’s side in the guise of a younf man. Said he to him, ‘Where are you going?’ Replied Yitzchok, ‘ To learn Torah.’ Said he, ‘And how will you learn Torah – in your lifetime or after your death? You poor child, and your poor mother! How many fasts did she fast until you were born, and now the old man has gone mad and is going to slaughter you.’ Said Yotzchok, “If it is so, then I shall not transgress the will of my Maker and the command of my father.’
Avrohom Avinu proceeded to Moriah in just this state of radical existential uncertainty. Maybe, just maybe, he proceeded anyway, compelled to follow the truth no matter what the cost, with the intention of testing both himself and G-d? Perhaps Avrohom wanted to see whether he was or was not deluded, to see if his G-d really is G-d?
And maybe, just maybe, all of the principals in this story passed this “test.” Which is quite a different test, and, in my opinion, a much more difficult one than would have been Avrohom’s blind obedience to what he might have assumed G-d’s words may have meant. This is borne out by the final words of the blessing given to Avraohom Avinu upon his offering of the ram instead of his son, since G-d places these words in the blessing angel’s mouth: “for you have listened to My voice” not “My words”.