"I delight to do thy will, O my God: yea, thy law is within my heart" (Psalm 40:8).
This remarkable testimony of David is actually also a Messianic prophecy, fulfilled completely only in Christ. Only as Messiah could He truly say: "My meat is to do the will of Him that sent me;" and, "I came down from heaven, not to do mine own will, but the will of Him that sent me;" "The works that I do in my Father's name, they bear witness of me" (John 4:34; 6:38; 10:25). "Wherefore when He cometh into the world, He saith . . . Lo, I come (in the volume of the book it is written of me,) to do thy will, O God" (Hebrews 10:5,7).
His heart was attuned perfectly to the will of God because God's law was written thereon, "not in tables of stone, but in fleshy tables of the heart" (II Corinthians 3:3). Even in the most trying circumstances to which any man could ever be subjected, He could pray: "Not my will, but thine, be done" (Luke 22:42).
By the indwelling Spirit of God, we also must seek to make the will of God our greatest delight. We are saved solely by grace, but this is not to deliver us from the burdensome constraints of God's holy law; as in the case of Christ Himself, He places His law in our hearts in order to enable us to love His law. "This is the covenant that I will make with them after those days, saith the Lord; I will put my laws into their hearts, and in their minds will I write them" (Hebrews 10:16).
Then we learn, like the psalmist, not to resist His will, but to love His will and to delight in His law. "O how love I thy law! It is my meditation all the day. . . . Thy testimonies have I taken as an heritage for ever: for they are the rejoicing of my heart. . . . I have longed for thy salvation, O Lord; and thy law is my delight" (Psalm 119:97,111,174). HMM