Genesis 12 marks a dramatic development in God’s dealings in human history. Up to that point, His purposes were directed at mankind in general. But in Genesis 12 He singles out one man, Abram, and begins to work in him and through him, making remarkable promises and binding Himself to fulfilling those promises with an irrevocable covenant. These promises would be repeated to Abraham’s son Isaac and his grandson Jacob, and would be referenced by Joseph just before his death at the end of the book of Genesis. The NT, commenting on this era in God’s dealings with man, states, “Now to Abraham and his seed were the promises made,” and points out that the law would come “four hundred and thirty years after” (Gal 3:16-17). This is one of the clear confirmations from the NT perspective on the dispensational view of God’s dealings with man over varying eras of time. The dispensation of promise, therefore, corresponds to the time of the patriarchs, taking us from Genesis 12 to Exodus 12 (or so), when the children of Israel are delivered from Egyptian bondage, brought across the Red Sea, and eventually receive the law through Moses at Mt. Sinai.
The dispensation begins with a direct revelation from God to Abram in Mesopotamia. Genesis 12 describes to us the Lord’s speaking with Abram in Haran, but Stephen tells us that “the God of glory appeared to our father Abraham when he was in Mesopotamia, before he lived in Haran” (Act 7:2 ESV). In Ur, God gave clear instruction to Abram to leave his land and his family, and to go “to the land that I will show you.” Then in Haran, God repeated this instruction, but added a promise: “I will make of you a great nation, and I will bless you and make your name great, so that you will be a blessing. I will bless those who bless you, and him who dishonors you I will curse, and in you all the families of the earth shall be blessed” (Gen 12:2-3 ESV). Basically, Abram was promised a land, a seed and divine blessing. In Genesis 15, God reiterates His promises to Abram, adding specific details regarding his seed (vv4-5) and the land (vv18-21). In Genesis 17, God speaks again to Abram, changing his name to Abraham to reflect his becoming the father of many nations. Also, God gives Abraham the clear instruction that he and all his male seed must be circumcised, providing an external token of the covenant relationship that existed between them and God.
The one specific responsibility placed on Abraham, and by extension, on his offspring, was to believe God. While elegantly simple, this command is truly profound. It is the only acceptable response to a promise from God, and it is the resounding commentary of the NT on this great man of faith: “Abraham believed God” (Rom 4:3); “He staggered not at the promise of God through unbelief; but was strong in faith” (Rom 4:20); “Abraham believed God, and it was accounted to him for righteousness” (Gal 3:6); “By faith Abraham, when he was called to go out into a place which he should after receive for an inheritance, obeyed; and he went out, not knowing whither he went” (Heb 11:8).
It is good for us to remember today, even in this age of grace, that believing God is our greatest responsibility. It is the first simple step in salvation, and it is meant to be the hallmark of our lives as His children. Faith, trust, obedience and dependence are the most basic requirements of a life that honours God and brings Him glory.
Sadly, as in every dispensation, failure is quickly seen as the narrative unfolds. Abram, the great man of faith at the beginning of Genesis 12, has by the end of that chapter left the land God promised him and journeyed into Egypt. While there, gripped with fear and uncertainty, he takes matters into his own hands, lies about his relationship with Sarai his wife, and only escapes disaster by divine intervention.
A few chapters later in Genesis 16 (after receiving further tremendous revelation and covenant promises from God in chapter 15), Abram once again takes matters into his own hands (spurred on by his wife Sarai). History has been forever impacted by the ramifications of that sad, sordid chapter in Abram’s life – his union with Hagar, the son Ishmael that sprang from that union, and the descendants that resulted.
Tragically, Abram’s failures would only be amplified and multiplied in his offspring. Isaac would mirror his father’s journey into Egypt and his deception concerning his wife. Jacob would have an unflattering characteristic streak of trickery throughout his life. And most tragic of all, Jacob’s descendants would ultimately be marked by such unbelief and rebellion that not one of the adults who were triumphantly redeemed from Egyptian bondage would be allowed to enter the land of promise (save Joshua and Caleb).
The early chapters of Exodus outline the bondage in Egypt that would grip the children of Israel for centuries. They would turn to the gods of the Egyptians and become idolatrous. Eventually, Egypt would feel the fury of God’s wrath as Pharaoh hardened his heart and would not hearken to God’s instruction. Most tragic, though, is the judgment on Abraham’s own descendants because of their rank rebellion and blatant unbelief. Hebrews 3 makes it crystal clear that God moved in direct retribution against an unbelieving people and “swore in His wrath” that they would not enter into His rest.
As in each of the dispensations, there is a thread of divine purpose that runs through the age of promise in spite of all man’s failure. God’s ultimate plan will proceed – it always does! The law would be given at Sinai to Moses, expressing God’s righteousness and providing beautiful foreshadowings of Christ’s ultimate provision. Joshua and Caleb would faithfully lead the people into their promised land. God’s covenants would remain unshakable and His ongoing revelation would continue.
There are vital practical lessons for us to learn from this dispensation of promise. The hallmark of Abraham’s life was that “he believed God.” All of us have abundant room for improvement in this regard! May we also learn the lessons, though, of the dangerous ramifications of unbelief and disobedience. Sin always has consequences – even for believers. It is sobering to see the far-reaching and long-lasting impacts resulting from single acts of disobedience in the life of a faithful man. May the Lord preserve each of us.
 All Scripture quotations in this article are from the KJV unless otherwise noted.