We are told, in Matthew, that there are 14 generations between Abraham and David, between David and captivity to Babylon, and between Babylon and Christ. This equals 42 generations between Abraham and Christ. It is suggested that there are about 2,160 years between Abraham and Christ. 2,160 divided by 42 equals 51.4 years per generation.
Other speculations about the length of a generation include 70 years, 100 years or even 40 years because that is how long the Israelites wandered in the wilderness. Some say the “final generation” began when Israel became a nation. Others contend that, while Israel becoming a nation was extremely important, it wasn’t until 1967, when it reclaimed Jerusalem, that it could be considered to have “bloomed.” It is clear that we cannot know for sure the timing of the Lord’s return. But it is obvious that we are close–close enough to count the days!