Confidence in the Covenant

In every covenant there are two parties. The very foundation of a covenant rests on the thought that each party is to be faithful to the part it has undertaken to perform.  

Unfaithfulness on either side breaks the covenant.  

It was so with the Old Covenant. God had said to Israel, "Obey My voice, and I will be your God" (Jeremiah 6:23; 11:4). These simple words contained the whole Covenant. When Israel disobeyed, the Covenant was broken.  

- an excerpt from Andrew Murray's "Covenants & Blessings"

Thus, the Old Covenant failed because of man's disobedience and lack of faithfulness! But what about the New Covenant?

For both the Old and New Covenants, God's side has always been secure because God is always faithful. God is the surety Himself that He will fulfill His part of the Covenants. Now, in this New Covenant, Christ is the surety for us that we will fulfill our part. Mankind, in and of ourselves, are unfaithful and incapable of maintaining our part of either of the Covenants. But God Himself, in His infinite grace and mercy, did what we could not do for ourselves.

God became a man so that He could become, for us, the ultimate representative for our side of the Covenant. As a result, God's faithfulness upholds both sides involved: His and man's.

The Father represents His own side and is faithful. The Lord Jesus, as the God-man, represents our side and is, too, faithful. Therefore, both sides are faithful to the part they have undertaken to perform. This guarantees the New Covenant to be an everlasting Covenant (Jeremiah 32:40) unlike the Old Covenant because of the person and work of the Lord Jesus Christ on our behalf! How mighty is our God!