This letter is one of the two greatest theological treatises of the New Testament. It is the ''Leviticus'' of the New Testament, detailing how the Lord Jesus Christ is both the fulfillment and the successor to all that had gone on before. This study will contrast conditional promises of the past with unconditional promises of the New Covenant: exchanging the shadows for substance. The Calvinist and Arminian viewpoints will be explored. This third of the trilogy on Habakkuk 2:4, ''The Just shall live by faith,'' addresses profound aspects of ''faith'' which challenge even the most diligent student.