Genesis 28:22 And this stone, which I have set for a pillar, shall be God’s house: and of all that thou shalt give me I will surely give the tenth unto thee.
Jacob recognized that what he had came from God. Notice him saying, of all that thou shalt give me. He knew that he was tithing because he was recognizing that God was giving it to him.
This is one of the first mentions of tithing. It is very similar to the time Abraham gave his tithe. They were recognizing that God was blessing them. That what they had came from God and so they were honoring Him with the tithe.
The question that you need to answer is, Do I recognize that what I have comes as a blessing from God? Do I tithe to honor the One I recognize as God who gives me all that I have? Do I not tithe because I do not recognize Him as God? At least this could get you thinking!