God wanted to do something for us, so He sent Jesus Christ, whose only purpose in life was to do the will of God, and the writer of the Book of Hebrews said,
By that will we have been sanctified through the offering of the body of Jesus Christ once for all (Hebrews 10.10).
“That will,” was the will of God that Jesus desired to do, as is evident from verse 9, and that will of God directed Jesus to offer His body for our sanctification. The offering of His body sanctified us, setting us apart for the Lord’s use. In other words, even as Jesus lived for doing the will of God, so should it be for us.