Exodus 13:1-2
At Succoth (12:37), the Lord instructed the Israelites about an act of devotion that was to become a part of Hebrew religious life.

13:1 The LORD said to Moses,

13:2 “Consecrate [set apart from common usage for holy purposes] to me every firstborn male [because God had delivered them from Egyptian bondage]. The first offspring of every womb among the Israelites belongs to me, whether man or animal.”

Exodus 13:11-16
13:11 “After the LORD brings you into the land of the Canaanites [emphasizes positive side of being set free; freed from bondage for a new relationship with God (19:3-6)] and gives it to you, as he promised on oath to you and your forefathers,

13:12 you are to give over [devote, surrender] to the LORD the first offspring of every womb. All the firstborn males of your livestock belong to the LORD.

13:13 Redeem [to buy back for a price] with a lamb every firstborn donkey [an unclean animal], but if you do not redeem it, break its neck [so that it could not be used or sacrificed]. Redeem [initially done by sacrificing an animal] every firstborn among your sons [“symbolized the Lord’s redemption of Israel and the firstborn’s devotion to God” (Advanced Bible Study)].

13:14 “In days to come, when your son asks you, ‘What does this [significance of Passover and consecration of the firstborn] mean?’ say [opportunity for instruction; cf. Ps. 107:2] to him, [summary of basic confession of faith of the Israelites; summary of historical events that brought about the exodus] ‘With a mighty hand the LORD [exodus was God’s doing, not man’s: divine deliverance not human escape] brought us out of Egypt, out of the land of slavery [condition from which the Lord delivered them].

13:15 When Pharaoh stubbornly refused to let us go, the LORD killed every firstborn in Egypt, both man and animal. This is why I sacrifice to the LORD the first male offspring of every womb and redeem each of my firstborn sons.’

13:16 And it will be like [in later times Jews wore phylacteries] a sign on your hand [a reminder “that what they reached out to do was to be in conscious recollection of what God had done for them and commanded them to do” (Dean)] and a symbol on your forehead [“indicates that what they looked at, how they saw and interpreted their world, was to be through this lens” (Dean)] that the LORD brought us out of Egypt with his mighty hand.”