Matthew 5:18

For verily I say unto you, Till heaven and earth pass away, one jot or one tittle shall in no wise pass away from the law, till all things be accomplished.

Jots ... tittles ... were the minutest markings and characters, forming parts of letters in the Hebrew alphabet. Christ here expressed full confidence in the Old Testament with the strong warning that it should never be disparaged or set at naught. The New Testament teaches that all of the prophecies of the Old Testament shall indeed be fulfilled (Luke 24:44), that its narratives are "written for our example" (1 Corinthians 10:11), and for our admonition and learning (Romans 15:4).

Here is the principle that the New Testament is essentially an extension of the Old, minus its types and shadows, plus an elevation and perfection of all its latent spirituality. However, the changes in Christ are so radically beyond anything ever dreamed of by the Old Testament prophets that the true connection tends to be obscured. The law of sacrifice was fulfilled in Jesus' death. The law of circumcision was replaced by that "circumcision not made with hands" (Colossians 2:11). The Passover gave place to the Lord's Supper and the sabbath day to the Lord's Day.