Many people believe the Israelites were enslaved in Egypt for 400 years based on what is written in Genesis 15:13 or 430 years based on what it says in Exodus 12:40. However, the Israelites couldn’t have been enslaved in Egypt for 400 or 430 years. The issue is that these numbers conflict with the math in the story and in actuality they couldn’t have been in Egypt for more than 350 years maximum.
I believe the 400 years in Genesis 15:13 and the 430 years in Exodus 12:40 are two different numbers for two different aspects of their Israelite’s history. Moses was 80 when the Israelites left Egypt (Exodus 7:7), Moses’ father Amram lived until age 137 (Exodus 6:20), and Moses’ grandfather Kohath lived until age 133 (Exodus 6:18). Kohath was one of the 66 people that left Canaan for Egypt with Jacob (Gen 46:8-26 [v11 mentions Kohath]). If Kohath, was born the year Jacob went to Egypt, and his son and grandson were each born the year their fathers died then,133+137+80 is a maximum of 350 years. So the Israelites COULDN’T have been in Egypt for more than 350 years. The 430 years in Exodus 12:40 are a count from the time Abraham received the promise at 75 years old, to the time Moses led the Israelites out of Egypt at age 80. This is explained by Paul in Galatians 3:16-17, and confirmed by Flavius Joseph, a Jewish historian from the 1st Century.
There are two explanations that I’ve seen for this discrepancy, one is that the KJV is the only correct translation of the Masoretic Text, and the other is that the Masoretic text is wrong and Septuagint/Samaritan Pentateuch got it right by including Canaan in Ex 12:40. Both explanations actually lead to the same conclusion so it does matter which side you take in the Masoretic Text vs Septuagint debate on this issue. For clarification, there are two versions of the old testament, the Hebrew Masoretic Text, and the Greek Septuagint. The Masoretic Text is written in Hebrew and is dated around 900-1100 AD. Some suspect that Jews tampered with it to cover up messianic prophecies (like Psalms 22:16). On the other side, there is the Septuagint (aka the LXX) which is a Greek translation of the Old Testament that goes back before the time of Jesus to around 300BC. Many favor this because it is older, but some suspect that this text was corrupted by the predecessors of the Sadducees. The Sadducees adopted some Greek philosophy and deny things like resurrection because it’s irrational according to Greek thinking. This has made some people suspicious of its consistency so they trust that the Jews preserved God’s word better in its original language at the end of the first millennium AD than the Greek Septuagint did pre-Christ. The Masoretic Text preserved the Hebrew language, in an era where the layman (non-religious scholar) Jews, spoken Hebrew had faded out of use and had been replaced by Aramaic. One of the biggest discrepancies is the ages of the patriarchs between Noah and Abraham. In the Masoretic Text, there are about 350 years between the flood and the birth of Abraham. In the Greek Septuagint, the ages of the patriarchs are all extended by around 750 years. Different people have different views and for the purpose of this discussion that is irrelevant, because again both sides actually agree on this issue. More on this topic here.
The Masoretic to KJV explanation:
Ex 12:40 (KJV) 40 Now the sojourning of the children of Israel, who dwelt in Egypt, was four hundred and thirty years.
Many modern English translations of Ex 12:40 say the Israelites were in Egypt for 430 years. However, in the KJV, Exodus 12:40 does not say that they dwelt in Egypt for 430 years but rather, the time of the “SOJOURNING OF the children of Israel, WHO dwelt in Egypt, was 430 years.” It basically defines who the children of Israel are by saying they are the people who are about to finally experience God’s promise to their ancestor Abraham, which was made 430 years ago because they are going to the promised land. Also, slaves don’t sojourn, since slaves are in bondage, so the sojourning started with Abraham. Abraham went to Canaan but he did not inherit it, he only sojourned in it as a foreigner. The land was promised to Abraham’s descendants (seed), not him specifically. This sojourning for 430 years is from the time of Abraham to the Exodus just as Paul says in Galatians 3:16-17. The text of Ex 12:40 does not say they had been IN Egypt for 430 years. To translate it as they lived in Egypt for 430 years is an incorrect rendering of the text. This kind of thing happens in various translations of the bible and is something to always pay attention to.
The Septuagint Explanation:
Ex 12:40 The people of Israel had lived in Egypt[and Canaan] for 430 years.
The pro-Septuagint side suggests that the Masoretic text dropped “and Canaan” from the verse. In the Septuagint and Samaritan Pentateuch, Ex12:40 says, “The people of Israel had lived in Egypt and Canaan (‘Canaan and Egypt’ in the Samarian version) for 430 years.” However, unlike other English versions, the KJV correctly translates the verse from the Masoretic Text, so we don’t need the Septuagint version of it. The LXX and Samaritan translations are later modifications designed to make it easier for people to understand that the Israelites were not in Egypt for 430 years. Those modern translations that suggest they were in Egypt for 430 most likely tried to mix these two versions together which made an incorrect mess.
How many years were they in Egypt?
We can add up the years and find out. Abraham’s promise was given at age 75 (Gen 12:3-7). Isaac was born 25 years later (Gen 21:5). When Isaac was 60 he had Jacob (Gen 25:26). Jacob went to Egypt 130 years later (Gen 47:9). So, 25 + 60 + 130 = 215, which is half of 430 years. So the second half of that 215 years make up the time the Israelites spent in Egypt, until the time of 80-year-old Moses and the Exodus. They weren’t enslaved until after Joseph died (Ex 1:8-11), which means they were in Egypt for 215 years but there were slaves for less than that.
How many years were they enslaved?
Joseph was 30 when the pharaoh appointed him vizier of Egypt (Genesis 41:40-46). Joseph was given this position after interpreting the pharaoh’s dream, which said there would be 7 years of abundance and 7 years of famine (Gen 41:53-54). Joseph’s family arrives two years into the 7-year famine (Gen 45:4-28). So Joseph was 39 (30+7+2) when Jacob came to Egypt. Joseph died at 110 (Gen 50:6), which is 71 years after Jacob comes to Egypt. So 215-71=144. So they were enslaved for 144 years max, and 80 years minimum. It’s possible that the Israelites weren’t enslaved the exact year Joseph died, but some time afterward when all of Jacob’s sons had passed. Their enslavement is not fixed to 144 or 80 but somewhere in between. Joseph died 64 years before Moses’ birth (144-80). If slavery started in-between I believe it would most likely be around 120 years before the Exodus because this is when Levi the last son of Israel died. Joseph asks his brothers before he died to make sure their descendants would take his body out of Egypt when they leave (Gen 50:24-26). This indicates that some if not all of his brothers outlived Joseph. The only other brother we have a death date for is Levi who died at 137 (Ex 6:16). Joseph was born at the end of the seven years of Jacob’s marriage (at age 91) to Rachel and Leah. We know this because Joseph was 39 when he reunited with Jacob who was 130 when he moved to Egypt and 130-39=91. Levi was the third son born to Jacob in the seven years he served under Laban while married(Gen 29:34), and Joseph was born at the end of it, so if there was at least one son born each year from all four of Jacob’s women, then Levi would be four years older than Joseph (7-3=4). This means that Levi was 114 when Joseph died at 110, so Levi died 23 years later (137-114). This means he died 41 years before Moses’ birth (64-23), and this would be 120 years before the Exodus.
The Genesis 15:13 prophecy conflict:
In Gen 15:13 it was prophesied that Abraham’s SEED (children/descendants) would be MISTREATED and ENSLAVED in a FOREIGN LAND for 400 years. “Foreign land” refers to both Canaan AND Egypt because Abraham was a foreigner in both since he is from Ur of the Chaldees. Canaan wasn’t his land, he just lived among them as a sojourner. His first “seed”, according to the promise was Isaac (Gen 17:17-22). Isaac was “mistreated” starting from the time he was being bullied by Ishmael in his weaning days (Gen 21:8-9). Paul even reminds us of the time Isaac was persecuted by Ishmael in Gal 4:29. Then at least 286 years after the promise, they were ENSLAVED in Egypt. In addition in Genesis 15:14, God says he will judge the nation [Egypt] for their enslavement of Abraham’s descendants, and they will leave [Egypt] with reparations. Then in verse 15, God says to Abraham, that he will join his ancestors in peace. This is in contrast to everything God just foretold, meaning Abraham himself is not included in the persecution or slavery, so it only applies to Isaac and later. Lastly, God says in Gen 15:16, that it is in the 4th generation (from the time they enter Egypt), that the Israelites will re-enter Canaan because by then the sins of the Amorites will warrant their destruction, just as the other Canaanite tribes. Generation one was Kohath who was with Jacob when they moved to Egypt, then Amram, then Moses, then the 4th generation was led by Joshua into the promised land. This is because Moses’s generation [the 3rd gen], lost the right to go into the promised land with the exception of Joshua and Caleb (Num 14:26-45, Num 20:12, Deut 32:48-52). So the next generation would enter under Joshua’s leadership.
Isaac was born 405 years before the Exodus from Egypt (430-25 years). Jewish Talmudic tradition says that weaning happens between 18 months and 5 years. If you subtract 5 from 405, then it’s 400 years. That corresponds to when Ishmael started bullying Isaac at his weaning ceremony which seems to have been on Isaac’s 5th birthday. This is why Gen 15:13 mentions a time 30 years less than the 430 years from Abraham’s promise to the Exodus. It seems that 30 years after the promise when Isaac turned 5 he was bullied by Ishmael while weaning, and that’s when Sarah kicked Hagar and Ishmael out for their persecution of Isaac.
Resources:
Jewish weaning tradition
An article on the pro-Masoretic explanation
Another pro-Masoretic article
Video on the pro-Septuagint argument