THen sang] Or, shall, or will sing. (According to the Grammaticall construction) which may implie, that as Moses sang then, when the Israelites were delivered, and the Egyptians destroyed; so the memoriall of this mercy and judgement should be kept up for the celebration of the glory of God in future times. Here in the first mention we finde of singing in the Scriptures, yet it is not like there was no singing in the world before this time, nor that the Patriarchs of precedent Ages praised not God in singing unto him; for many things were done which are not recorded in the Scriptures: as (no doubt) the Fathers before the flood kept a weekly Sabbath, for it was ordained at the beginning of the world, upon such grounds, as concerned them as much as any of their Successours: yet we read not of the practise of the Sabbaths observation, untill the 16. of Exod.
Moses and the children] The ong composed by Moses, and garnished with many patheticall, and rhetoricall expressions might be sociably sung by himselfe, and the people; who (if they had not a competent number of copies of it, to read it) might have it repeated by parts unto them, so they might sing it altogether, (as the manner is in many Churches of the Christians:) or he himselfe might sing it for himselfe, and them; as the prayers of a publique Minister in the publique execution of his Office, are the prayers of the people, (though he onely speake) while he doth it for them, as well as for himselfe, and with their consent.
this song unto the Lord] Wherein they give him the whole glory of his owne victory, magnifying his justice upon Pharaoh, and the Egyptians, and his mercy on his own people.