Jubilees 17:16
15 And it came to pass in the seventh week, in the first year thereof, [2003 A.M.] in the first month in this jubilee, on the twelfth of this month, there were voices in heaven regarding Abraham, that he was faithful in all that He told him, and that he loved the Lord, and that in every affliction he was faithful. 16 And the prince Mastêmâ came and said before God, 'Behold, Abraham loves Isaac his son, and he delights in him above all things else; bid him offer him as a burnt-offering on the altar, and Thou wilt see if he will do this command, and Thou wilt know if he is faithful in everything wherein Thou dost try him. 17 And the Lord knew that Abraham was faithful in all his afflictions; for He had tried him through his country and with famine, and had tried him with the wealth of kings, and had tried him again through his wife, when she was torn (from him), and with circumcision; and had tried him through Ishmael and Hagar, his maid-servant, when he sent them away. 18 And in everything wherein He had tried him, he was found faithful, and his soul was not impatient, and he was not slow to act; for he was faithful and a lover of the Lord.
Pseudo Philo Biblical Antiquities 32:2
1 Then Deborah and Barak, son of Abinoam, along with all the people, sang a hymn to the Lord on that day, saying: "See, from on high the Lord has shown us his glory, just as he did in the past when he sent forth his voice to confuse the languages of men. He selected our nation, rescued Abraham our forefather from the fire, chose him above all his brothers, shielded him from the fire, delivered him from the bricks of the tower's construction, and gave him a son in his old age, brought him from a barren womb, and all the angels envied him, and the commanders of the hosts were jealous of him. 2 When they were jealous of him, God said to him: "Sacrifice for me your child and offer for me that which I gave to you." Abraham did not contradict him and immediately went forth. As he went, he said to his son: "Now, my son, I offer you for a burnt offering and surrender you to him who gave you to me."
Notes and References
"... But even this inspiring narrative raised questions for early interpreters. Why, to begin with, should God want to test Abraham? Certainly not in order to find out whether Abraham was worthy. For, as we have just seen, Abraham had already proven himself worthy many times in the past ... In seeking the answer to these questions, interpreters looked to other parts of the Bible, in particular, to the book of Job, another biblical figure whom God had tested. In his case, however, the test was initiated not by God but by Satan, who in effect challenged God's high opinion of Job: 'Do some harm to him, indeed, afflict all that he has, and then see if he does not curse You to Your face' (Job 1:11). To ancient interpreters it seemed plausible that, with regard to Abraham as well, God may have received a challenge from Satan or some other angel(s) ..."
Kugel, James L. The Bible as it Was (pp. 170-171) Harvard University Press, 1998