3:40-51 The number of the first-born, and that of the Levites, came near to each other. Known unto God are all his works beforehand; there is an exact proportion between them, and so it will appear, when they are compared together. The small number of first-born, over and above the number of the Levites, were to be redeemed, and the redemption-money given to Aaron. The church is called the church of the first-born, which is redeemed, not as they were, with silver and gold; but, being devoted by sin to the justice of God, is ransomed with the precious blood of the Son of God. All men are the Lord's by creation, and all true christians are his by redemption. Each should know his own post and duty; nor can any service required by such a Master be rightly accounted mean or hard.And Moses numbered, as the Lord commanded him,.... No doubt assisted by others, though not mentioned:

all the firstborn among the children of Israel; which some think were only those that were born since they came out of Egypt, as Bonfrerius, Bishop Patrick, and others.