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Psalm 40
God Sustains His Servant.
6Sacrifice and offering thou hast no delight in; Mine ears hast thou opened: Burnt-offering and sin-offering hast thou not required.
7Then said I, Lo, I am come; In the roll of the book it is written of me:
8I delight to do thy will, O my God; Yea, thy law is within my heart.
Psalms 40:6-8 (ASV)