To God, the greatest sin we can commit is idolatry. He devoted several of the Ten Commandments to that issue. One would think that murder or adultery might be as heinous or more so. But that is not so.
That is because our life and behavior flow out of our walk with God. When our loyalty to God wanes, we are vulnerable to every sin. David committed both adultery and murder, yet God declared that he was loyal to God. That is because, though David sinned abominably, his love for God always drove him back to repent and to return to God. But when our heart becomes captive to other gods, then we become estranged from the one Person who could save us.
Once Solomon’s heart went after other gods, no amount of prophecy or warnings could deter him. His heart became calloused and insensitive to divine promptings.David, though he sinned greatly, always had a heart that could be drawn back to God. As a result, David never strayed too far or for too long.
You might feel pleased that you have followed God for many years. Yet that will not matter if your heart is being drawn to other gods.