Acts 7:4

Obeying God’s call, Abraham left Mesopotamia, specifically Ur of the Chaldeans (cf. Genesis 15:7; Joshua 24:3; Nehemiah 9:7), and settled temporarily in Haran, near the top of the Fertile Crescent. After Abraham’s father Terah died, God directed Abraham south into Canaan, the land the Jews occupied in Stephen’s day (Genesis 12:5).

"A comparison of the data in Genesis (Genesis 11:26; Genesis 11:32; Genesis 12:4) seems to indicate that Terah lived another 60 years after Abraham left [Haran]. . . . The best solution seems to be that Abraham was not the oldest son of Terah, but was named first because he was the most prominent (Genesis 11:26)." [Note: Kent, p. 68.]

"It is more likely that Stephen is using an old and alternate Jewish tradition here that has left its trace in the LXX and the Samaritan Pentateuch, although the possibility also exists that Genesis 11:26 should be read differently, so that the MT and the LXX are closer than it might appear." [Note: Bock, Acts, p. 284.]

The father of Judaism was willing to depart from where he was to follow God into unknown territory on the word of God alone. The Jews in Stephen’s day were not willing to depart from where they were in their thinking even though God’s word was leading them to do so, as Stephen would point out. Stephen wanted them to follow Abraham’s good example of faith and courage.