If one considers and accepts that the Genesis narrative does allow for this account by Stephen, then any supposed difficulties or contradictions vanish. It would be incorrect to assert that Stephen somehow got the account of Abraham and his call wrong or that he was simply mistaken in his telling of the story, or that Luke was mistaken in his report. This is especially important if when considering that Luke, as the author of Acts, clearly presents Stephen as speaking “under the inspiration” if you will, as Luke intends to make the point that it is Jesus Himself that has given Stephen the words he is to speak.
Luke knows what he is doing in his writing, and would naturally have in mind what he has previously written, which was “But before all this, they will seize you and persecute you, handing you over to synagogues and prisons. You will be brought before kings and governors because of My name. This will be a time for you to serve as witnesses (martyrs). Therefore be resolved ahead of time not to make your defense. For I will give you the words along with the wisdom that none of your adversaries will be able to withstand or contradict” (21:12-15). This plays out in Stephen’s trial.
Obviously, Jesus, if He is indeed speaking through Stephen (presumably via the Spirit of the Creator God), which appears to be the conclusion that Luke desires his hearers to reach, is going to get the story of Abraham correct. That said, it is interesting that Stephen, when recounting the history of Israel, omits the portion of the call in which Abraham is directed to leave his father. This is probably a standard bit of smoothing out of the Abraham narrative, since it is clear that, though the call came at an earlier point in his life, according to the Genesis narrative, Abraham did not leave his father until after his father had died. The point is, the call came to Abraham while his father was still alive, not after he is dead, as one might presume if simply reading Genesis and contemplating a straight chronological progression from the end of chapter eleven to the beginning of chapter twelve, which, if read in such a way, makes the call to leave his father make little sense.
So yes, Abraham is given a difficult choice. Will he stay with his father or will he leave his father, as the Creator God has directed him to do. Clearly, Abraham chose to stay with his father. In a sense then, and it is okay to point these things out because Abraham is not to be deified, it can be asserted that Abraham failed in this area. Of course, Abraham failed in other areas too, so it’s not as if this is groundbreaking news. Where Abraham failed, in that he did not undertake the journey in response to the Creator’s call until after his father had died, these disciples succeeded in their response to the call, leaving their father when called. Painting a big picture then, where Adam, Abraham, and Israel had failed, Jesus and those that follow after Him will succeed, with this demonstrated in these disciples (leaving their father when called by Jesus (the second Adam/the one that will complete Abraham’s mission/the new Moses/the embodiment of Israel/the incarnate Creator God).
Though there is no reason whatsoever to take a dogmatic stance here, thinking about the call of the disciples in conjunction with the call of Abraham, along with the similarities and differences to be found, gives a new twist to one of Jesus’ most provocative statements, as recorded by both Matthew and Luke. Using Luke’s treatment, one reads that “Jesus said to another, ‘Follow Me.’” (9:59a) This, according to this particular theory of engagement with this Gospel, is going to have brought Abraham’s call to the minds of Luke’s audience. What is the response to Jesus’ call? “He replied, ‘Lord, first let me go and bury my father.’” (9:59b)
Might this rather standard excuse for not taking action be an oblique reference to Abraham? If Abraham, the progenitor of the covenant people, didn’t do something that the covenant God had commanded him to do until after his father died, surely his descendants should not be expected to do so. To this, Jesus responds, “Let the dead bury their own dead, but as for you, go and proclaim the kingdom of God” (9:60). Perhaps Jesus is here insisting that His countrymen go beyond the example provided to them by Abraham? For Luke’s purposes (and Matthew’s), the audience that is hearing his construction of a Jesus narrative, has already seen two disciples respond to His God-to-Abraham-like call by leaving their father, and here, with the addition of another story from Jesus’ life, he builds on that premise.