For I will be merciful to their unrighteousness, and their sins and their iniquities will I remember no more.
—Hebrews 8:12

In the book of Hebrews, Christ is called the “Mediator of a better covenant, which was established upon better promises” (verse 6). In Him the two parts of the covenant find their fulfillment.

First of all, He came to atone for sin, so that its power over man was destroyed and free access to God’s presence and favor was secured. With that came the fuller blessing: the new heart, freed from the power of sin, with God’s Holy Spirit breathing into it the delight in God’s law and the power to obey it.

These two parts of the covenant can never be separated. And yet, unfortunately, many people put their trust in Christ for the forgiveness of sin but never think of claiming the fullness of the promise of being God’s people and knowing Him as their God. They do not allow God to bring into their experience a new heart cleansed from sin, with the Holy Spirit breathing into it such love and delight in God’s law, and such power to obey, that they have access to the full blessing of the new covenant.

Jesus is “the Mediator of the new testament” (Hebrews 9:15), in which the forgiveness of sin is in the power of His blood, and in which the law is written in hearts by the power of His Spirit. Oh, if only we could understand that, just as surely as the complete pardon of sin is assured, so the complete fulfillment of the promises may be expected, too: “I will put my fear in their hearts, that they shall not depart from me” (Jeremiah 32:40); “I will…cause you to walk in My statutes, and you will keep My judgments” (Ezekiel 36:27).

But God has said, “Behold, I am the LORD, the God of all flesh: is there any thing too hard for Me?” (Jeremiah 32:27). He spoke these words to Jeremiah in regard to the new covenant. The new covenant requires strong, wholehearted desire for a life wholly given up to God. It means we must set aside all our preconceived opinions, and in faith believe in the mighty power of God. It means a surrender to Jesus Christ, a willingness to accept our place with Him, crucified to the world, to sin, and to self. It means a readiness to follow Him at any cost. Succinctly, the new covenant means wholehearted acceptance of Christ as Lord—heart and life wholly His. “I, the LORD, have spoken it, and will do it” (Ezekiel 22:14).