Jacob made a solemn promise: “If God is with me and protects me on this trip I’m taking, and gives me bread to eat and clothes to wear, and I return safely to my father’s household, then the Lord will be my God. This stone that I’ve set up as a sacred pillar will be God’s house, and of everything you give me I will give a tenth back to you.”
This comes directly after God appears to Jacob at Bethel and promises to not only be with Jacob, but to protect him from all danger and give him numerous descendants.
This also shows an immature faith on the part of Jacob. He already knows the stories of how God had worked in his grandfather Abraham’s life and how he worked in his father Isaac’s life. Now he had an amazing mystical experience with God who came and gave a blessing to Jacob far beyond even the blessing Isaac gave him, and Jacob believed, but not fully. Jacob felt that he had to initiate a covenant with God, rather than be the recipient of the covenant from God. Jacob’s words here imply that it would be a privilege for God to have a worshiper and devoted follower such as Jacob. So Jacob offers terms to God for why he would worship.
What is sad about this is that God offered no conditions on what he said to Jacob, yet Jacob offers conditional devotion to God. That is what bargaining with God ultimately is: conditional devotion to God. It is not accepting God for who he is and offering ourselves without reserve to love the Lord with all our heart, mind, soul, and strength. It is saying, “God, if you give me what I want, I’ll give you what I think you want.”
Be careful when tempted to bargain with God. His blessings can far exceed our wildest imaginations, and all we have to do is love. We do not have to earn his blessing, just as Jacob did not have to earn the blessing. God already earned our love by sacrificing everything he has and is for us on the Cross.