11 "And it shall be, when the Lord brings you into the land of the Canaanites, as He swore to you and your fathers, and gives it to you, 12 that you shall set apart to the Lord all that open the womb, that is, every firstborn that comes from an animal which you have; the males shall be the Lord's. 13 But every firstborn of a donkey you shall redeem with a lamb; and if you will not redeem it, then you shall break its neck. And all the firstborn of man among your sons you shall redeem. 14 So it shall be, when your son asks you in time to come, saying, 'What is this?' that you shall say to him, 'By strength of hand the Lord brought us out of Egypt, out of the house of bondage. 15 And it came to pass, when Pharaoh was stubborn about letting us go, that the Lord killed all the firstborn in the land of Egypt, both the firstborn of man and the firstborn of beast. Therefore I sacrifice to the Lord all males that open the womb, but all the firstborn of my sons I redeem.'
Matthew Henry's Commentary on Exodus 13:11-15
Commentary on Exodus 13:11-16
(Read Exodus 13:11-16)
The firstlings of beast not used in sacrifice, were to be changed for others so used, or they were to be destroyed. Our souls are forfeited to God's justice, and unless ransomed by the sacrifice of Christ, will certainly perish. These institutions would continually remind them of their duty, to love and serve the Lord. In like manner, baptism and the Lord's supper, if explained and attended to, would remind us, and give us occasion to remind one another of our profession and duty.