The people saw that Moses was taking a long time to come down from the mountain. They gathered around Aaron and said to him, “Come on! Make us gods who can lead us. As for this man Moses who brought us up out of the land of Egypt, we don’t have a clue what has happened to him.” Aaron said to them, “All right, take out the gold rings from the ears of your wives, your sons, and your daughters, and bring them to me.” So all the people took out the gold rings from their ears and brought them to Aaron. He collected them and tied them up in a cloth. Then he made a metal image of a bull calf, and the people declared, “These are your gods, Israel, who brought you up out of the land of Egypt!”
God had just given Moses the Covenant and the plans for how to make the Tabernacle so that his presence would be in the midst of Israel forever. And here the people would rather try to make their own god than receive what God was going to freely do for them–dwell with them. They schemed, planned, and worked giving personal resources (gold that was given to them by the Egyptians at God’s instigation no less) to do something that was going to happen for them by God’s initiative.
Many times within the life of the Church congregations do this same act. They may not physically make idols and worship them, but they do take matters into their own hands to try and create something that may or may not be what God wants. Rather than wait on the Lord and be guided by God into being and doing what God wants, they decide to take action and then ascribe that decision to the Lord. It is the difference between praying for God’s leading and then taking action and making a decision and then praying for God to bless the decision.