In Exodus 20:3 and Deuteronomy 5:7 the Israelites were warned not to serve other gods. The exact words were, “You shall have no other gods before me”. The true and real God is a jealous God who makes it clear that those who follow Him cannot put other people or things as a priority in their lives.
Most people today in our civilized world wouldn’t think of putting up an idol in their homes made out of wood or metal like the Israelites ended up doing, so we think that this cannot be problematic for us. The spirit behind this kind of disobedience is still with us today and will always be an issue to be dealt with. There are so many things that can become a priority in our lives that replace God. It can be as simple as how we spend our time and money and where we use our talents.
I do believe when a person decides to get into a right relationship with God, they will have a desire to change their ways and will accept the forgiveness offered through the sacrifice of Jesus.
Then, as they grow in their faith there will be temptations and opportunities to allow other things to become a priority.
God, through His Holy Spirit, is faithful to convict us and to give us the power to avoid those temptations and to help us keep God as our Lord and King.