The Bible is helpful to provide an ample amount of testimonies that describe God having control of and being aware of all circumstances, which allows Him to fulfill all of His promises. There are a lot of people who have made promises, but circumstances have often prevented them from fulfilling them, even though they may have worked really hard to see them fulfilled. People are naturally limited in this way. Though a person may desire to honor their promise, people and/or circumstances can often keep promises from being fulfilled. God does not have this problem!
In Genesis 31:1-21 the Bible explains that Jacob sought to separate from Laban. The testimony begins by explaining that there was an environment of jealousy and resentment from Laban's family. Though Laban began with the choice flock and herds, God was blessing Jacob so that his flocks and herds became more superior in quality and more abundant than Laban's. The Bible explains that Laban's sons took notice and began to get bitter. They began to accuse Jacob of various things and Laban's attitude towards Jacob began to change. Though Laban first appreciated Jacob because he was a beneficiary of Jacob's blessings, Laban began to resent Jacob because Jacob was flourishing more.
The Bible explains that Jacob took notice of the attitude changes amongst Laban's family. Therefore, Jacob met with his wives, Leah and Rachel, and suggested that they leave. Jacob explained that he had a dream, and in that dream, he tended to various types of flocks; yet no matter the types of flocks, they flourished. Jacob first tended to spotted sheep and all the sheep became quality spotted sheep. Then Jacob tended to streaked sheep, and all the sheep became quality streaked sheep. The dream that Jacob had made Jacob aware that God was doing the multiplying and that no matter what, this was what God was going to do. Though Jacob was employing certain techniques to tend to his flocks and herds, Jacob recognized that God was ultimately responsible for the increase, and that was not going to change. In other words, Jacob recognized that God was working to fulfill His promises, and there was nothing Jacob could do about it. Hence the jealousy between Laban and Jacob wasn't going to go away.
Jacob suggested to his wives that they move. In order to get away from the jealousy and resentment of Laban, Jacob suggested to Leah and Rachel that they should move to another land - the land that Jacob was born in that God had originally promised to Abraham. Leah and Rachel acknowledged the circumstances. They realized they were not going to receive any inheritance from their father. They realized that Jacob had become more wealthy than their father. They realized that Laban was treating his own daughters like outsiders. They realized that there was nothing in their homeland that they were attached to, so they had no reason to object to moving into Canaan with Jacob. Thus, as God commanded Jacob to go back to Canaan in his dream, Jacob made the efforts to do so in obedience.
If one examines the circumstances of Jacob in Genesis 331:1-021 and compares them to the promises God made to Abraham, Isaac, and later Jacob, the situation becomes clear. The reason that Jacob experienced his trials was because God wanted to take Jacob back into the land that He promised. God promised that He would make Abraham's family into a great nation. Hence, God used the deception of Laban to give Leah to Jacob, and the love of Jacob to wait for Rachel, and the contention of Leah and Rachel to produce 11 boys that would become "the children of Israel." Additionally, God used the greed of Laban to multiply Jacob and make him into a great nation. Since Laban wanted to keep Jacob around because of the way that God blessed him, God used Laban's resources to multiply Jacob's wealth. God promised that he would give Abraham's family the land inheritance of Canaan. Hence, God used the spite and jealousy of Laban as a reason for Jacob to leave Haran and go back to Canaan.
How does one fulfill eternal promises? If circumstances are always changing, it forces one to continually be on top of the circumstances to ensure they line up in favor of the promises; otherwise the circumstances prevent the promises from being fulfilled. How can one manage this kind of attention to detail eternally? Mankind is unable to do so. Yet the scriptures clearly show that God is able. His eternal nature allows Him to exist long enough to make eternal promises. His omniscience allows Him to know all things so that He can work in the midst of changing circumstances and have the wisdom to correct the course that leads to the fulfillment of His promises. His omnipotence allows Him to have control over circumstances so that He can intercede in various events through dreams and visions if necessary (as with Jacob) to move people from place to place according to His promises. His mercy allows mankind to live long enough to receive the benefits of His promises in spite of circumstances that should disqualify one as a beneficiary. His faithfulness keeps Him focused on the fulfillment of His promises so that He is not distracted or uninspired to stray from the fulfillment of His promises. These attributes make God incredibly unique and awesome! Thus, when God makes a promise, rest assured that it will be fulfilled, one way or another, no matter what the circumstances look like!