Sacrifice and offering thou didst not desire. Will the right return be by sacrifices and burnt offerings? No, the psalmist answers to himself; it is not these which God really "desires." Samuel had already preached the doctrine, "Behold, to obey is better than sacrifice, and to hearken than the fat of rams" (1 Samuel 15:22).
David goes further. Apart from a spirit of obedience, sacrifice and offering are not desired or required at all; rather, as Isaiah says, they are a weariness and an abomination (Isaiah 1:11, Isaiah 1:12).
The one thing needed is obedience—a cheerful, willing obedience to all that God reveals as his will. Mine ears hast thou opened. Either, "Thou hast taken away my deafness, and given me ears open to receive and embrace thy Law;" or, perhaps, with special reference to Exodus 21:6 and Deuteronomy 15:17, "Thou hast accepted me as thy voluntary servant, and bored through mine ear, to mark that I am thy servant for ever."
Burnt offering and sin offering hast thou not required. Of the four kinds of offering mentioned in this verse, the first ( זבח) is the ordinary offering of a victim at the altar in sacrifice; the second ( מנחה), the meat offering of flour, with oil and frankincense accompanying it; the third ( עולה) is the "whole burnt offering," representative of complete self-sacrifice; and the fourth ( חטאה), the "sin offering," or "trespass offering," of which the special intention was expiation.