Pseudo Philo Biblical Antiquities 18:5
4 And in the night God said unto him: Who are the men that are come unto thee? And Balaam said: Wherefore, Lord, dost thou tempt the race of man? They therefore cannot sustain it, for thou knewest more than they, all that was in the world, before thou foundedst it. And now enlighten thy servant if it be right that I go with them. 5 And God said to him: Was it not concerning this people that I spake unto Abraham in a vision saying: Thy seed shall be as the stars of heaven, when I raised him up above the firmament and showed him all the orderings of the stars, and required of him his son for a burnt offering? and he brought him to be laid upon the altar, but I restored him to his father. And because he resisted not, his offering was acceptable in my sight, and for the blood of him did I choose this people. And then I said unto the angels that work subtilly: Said I not of him: To Abraham will I reveal all that I do?
Apocalypse of Abraham 20:3
1 And the Eternal Mighty One said to me, “Abraham, Abraham!” 2 And I said, “Here am I!” 3 And he said, “Look from on high at the stars which are beneath you and count them for me and tell me their number!” 4 And I said, “Would I be able? For I am [but] a man.” 5 And he said to me, “As the number of the stars and their host, so shall I make your seed into a company of nations, set apart for me in my lot with Azazel. 6 And I said, “Eternal Mighty One! Let your servant speak before you and let your fury not rage against your chosen one.
Notes and References
"... In the ancient world, Chaldea was famous for one thing in particular: it was the home of astronomy and astrology. So great was the association between Chaldea and the study of the stars that the very word 'Chaldean' came to mean 'astronomer' in both Aramaic and Greek. Many interpreters therefore naturally assumed that Abraham the Chaldean must himself have been something of an astronomer. And so a number of early sources present Abraham as both a learned astronomer and a teacher of this occult lore to others ..."
Kugel, James L. The Bible as it Was (pp. 139-140) Harvard University Press, 1998
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