It was just four hundred and thirty years from the promise made to Abraham (as the Apostle explains it, Galatians 3:17,) at his first coming into Canaan, during all which time the Hebrews, were sojourners in a land that was not theirs, either Canaan or Egypt. So long the promise God made to Abraham lay dormant and unfulfilled, but now, it revived, and things began to work towards the accomplishment of it. The first day of the march of Abraham's seed towards Canaan was four hundred and thirty years (it should seem, to a day) from the promise made to Abraham, Genesis 12:2. I will make of thee a great nation.
Related Commentaries of Exodus 12:40
Exodus 12:40
40 Now the sojourning of the children of Israel, who dwelt in Egypt, was four hundred and thirty years.