Genesis 15:6
5 The Lord took him outside and said, “Gaze into the sky and count the stars—if you are able to count them!” Then he said to him, “So will your descendants be.” 6 Abram believed the Lord, and the Lord credited it as righteousness to him. 7 The Lord said to him, “I am the Lord who brought you out from Ur of the Chaldeans to give you this land to possess.”
Jubilees 14:6
4 He brought him outside and said to him: ‘Look at the sky and count the stars, if you can count them.’ 5 When he had looked at the sky and seen the stars, he said to him: ‘Your descendants will be like this.’ 6 He believed the Lord, and it was credited to him as something righteous. 7 He said to him: ‘I am the Lord who brought you from Ur of the Chaldeans to give you the land of the Canaanites to occupy forever and to become God for you and your descendants after you.’
Romans 4:3
1 What then shall we say that Abraham, our ancestor according to the flesh, has discovered regarding this matter? 2 For if Abraham was declared righteous by works, he has something to boast about—but not before God. 3 For what does the scripture say? “Abraham believed God, and it was credited to him as righteousness.” 4 Now to the one who works, his pay is not credited due to grace but due to obligation.
Notes and References
"... Compared to the Masoretic text of Genesis 15:1–6, Jubilees 14:1–6 has the addition of the dating (Jubilees 14:1), some other small additions (elements in Jubilees 14:2-5), some small omissions (Genesis 15:3, and elements in Genesis 15:3-4), and some variations (elements in Jubilees 14:1-6). Some of the differences are possibly due to the fact that the text of Genesis the author of Jubilees uses is a text different from the Masoretic one. The suffix (“to him”) to the verb in Jubilees 14:4 occurs also in the Peshitta, Septuagint, old Latin, and Ethiopic text of Gen 15:5. (See also Romans 4:3; Galatians 3:6; James 2:23; 1 Maccabees 2:52) The passive form in Jubilees 14:6 (“it was counted”) occurs also in the Peshitta, Septuagint, old Latin, and Ethiopic text of Genesis 15:6. Therefore, we cannot consider these deviations as variations of the scriptural text ..."
van Ruiten, J. Abraham in the Book of Jubilees: The Rewriting of Genesis 11:26-25:10 in the Book of Jubilees 11:14-23:8 (p. 123) Brill, 2012