You shall not wrong one another, but you shall fear your God, for I am the Lord your God.
A natural outcome of loving, respecting, worshiping, and obeying God is that our human relationships are marked by fairness, concern, and proper respect for other people. This principle was meant to govern the social lives of ancient Israel. At issue in this Leviticus passage were the sabbath years and the celebration known as Jubilee. Every seventh year the agricultural practice was to let the ground lay fallow. God would supply abundantly the year before this so that the land and the people could worship Him with an entire year of sabbath rest. Every seventh sabbath year (a 49 year cycle) was to be a year of Jubliee, a once in a lifetime event in which all land debts were cancelled. Slaves were released from bondage. Contracts ended in celebration of God's liberation of Israel.
God warned Israel not to humanly negotiate around these standards. As Jubilee approached, it would be tempting not to loan money to a needy person, or to make a sale of property, or it might be easy to raise interest rates in preparation for the year of "losing" everything. But God wanted this principle of fairness and social justice to flow from His people. Jubilee was a way of keeping materialism at bay. It was a form of worship. It said, in a way, "God is so much greater than our stuff!" But if we use people to keep our stuff, we aren't really fearing God.
There are no social mechanisms in my culture to create this awareness like the year of Jubilee did. We are just the opposite. We are all taught to be selfish with our stuff. We applaud greedy real estate moguls while homelessness is a growing issue in cities all around the world. We open new restaurants while some people never get a decent nutritious meal their entire lives. We worry over banks and retirement planning thinking money is what takes care of us. And we miss truly worshiping God and really caring for people. Jesus was right: You can't worship both God and money.