I delight to do thy will, O my God: yea, thy law is within my heart.
I delight to do thy will - (John 4:34; John 6:38; John 17:4.) As the Son saith, "I delight" to do the Father's will, so the Father saith of the Son (Isaiah 42:1), "Behold my servant ... mine elect, in whom my soul delighteth."
Yea, thy law is within my heart ( mee`aay (H4578)) - literally, 'in the midst of my bowels,' or 'inward parts.' None but Christ realized this perfectly. Old Testament believers, in some measure, had the law in their heart (Psalms 37:31; Deuteronomy 6:6; Deuteronomy 27:3; Proverbs 3:3; Proverbs 7:3); yet the fullness of the Spirit, whereby the law was written in the hearts of God's people (Jeremiah 31:33), was reserved for the times of the Gospel of Jesus, in whose heart first, as man, the law was perfectly written (Matthew 5:17; Romans 10:4). Christ alone fully reconciles the opposites (which would be, as applied, to a mere man like David, self-contradictions) - 'delighting to do God's will,' and having 'the law within His heart,' and yet encompassed with 'innumerable iniquities' (not His own, but ours, laid on Him by imputation). In a less strict sense, the seeming opposites hold good of the believer: Romans 7:22-23, "I delight in the law of God after the inward man: but I see another law in my members warring against the law of my mind, and bringing me into captivity to the law of sin."