Annual Reading Schedule - Torah Given Through Mosheh - Week 4 - Walk Before Me And Be Perfect (Genesis 14:16-19:28)

Genesis 15:13 says they would be afflicted for 400 years, but the timeline study I did came out to estimating slavery only lasted, at the most, 144 years. This is based on the starting point of slavery being the year after Yoseph's death, and the ending point being 430 years after the promise was given to Avraham (Galatians 3:17).

Yoseph's death is calculated to be in the year 2369 and the promise given to Avraham is calculated to be 2083, the year Terach died and he left Charan. 2083 + 430 = 2513. 2513 – 2369 = 144 years of slavery.

Perhaps the 400 years is referring to one hundred years from each of the 4 generations in slavery? Genesis 15:16 says they return in the 4th generation. Perhaps Genesis 15:16 is referring to the generations of Lewi (who lived 137 years), Qehath (who lived 133 years), Amram (who lived 137 years), and Mosheh and Aharon (who lived 120 and 123 years)? These periods of time obviously overlap, so I'm not sure on what the 400 years or the 4 generations refer to specifically, just presenting some possibilities based upon the timeline studies I've done.

Or, more likely I think, perhaps the 400 years is referring to the time period from 30 years after the promise until the exodus? The reason why that is possible is because Genesis 15:13 also mentions being "sojourners" as well, not just the affliction of slavery. Therefore, perhaps the 400 years includes not just the time of hard bondage in slavery, but also time of sojourning. That is what I think is most likely the best explanation for the 400 years mentioned is that it may include also the time of being sojourners, since that is also mentioned in that verse.