The Book of Exodus introduces that new epoch in the scriptural history of sacrifices when they began to be regulated by fixed laws, to be part of a national economy.
I. The offering of the firstborn was the dedication and consecration of the whole Jewish nation. The firstborn represented its strength, its vitality, its endurance. This act signified that its strength lay only in its dependence on God's strength, that its vitality came from the life which is in Him, that it would endure from generation to generation, because He is the same and His years fail not.
The calling of the Israelites was the calling to confess a Redeemer of Israel, a righteous Being who had brought out their fathers from the house of bondage.
II. Moses taught the people that by looking upon themselves as beings surrendered and sacrificed to the God of truth, the Deliverer of men, by feeling that they held all the powers of their minds and bodies as instruments for the great work in which He is engaged, thus they might be a nation indeed, one which would be a pattern to the nations, one which, in due time, would break the chains which bound themto visible and invisible oppressors.
III. When once we understand that we are witnesses for God, and do His work, self-sacrifice can never be an ambitious thing a fine way to get the reputation of saints or the rewards of another world. It will be regarded as the true ground of all action; that on which all the blessed relations of life stand; that which is at the same time the only impulse to and security for the hard and rough work of the world.
F. D. Maurice, The Doctrine of Sacrifice deduced from the Scriptures,p. 49.
References: Exodus 13:17; Exodus 13:18. J. Jackson Wray, Light from the Old Lamp,p. 83; W. Landels, Christian World Pulpit,vol. iii., p. 184; G. Matheson, Moments on the Mount,p. 6. Exodus 13:17-19. Parker, vol. ii., p. 316. 13:17-14:4. Expositor,2nd series, vol. vi., p. 448.