"When God was leading his people through the wilderness and laying down his laws, he gave instructions for things that were to be set up for worshiping him and remembering his deeds. He gave detailed directions for setting up the tabernacle. Often, he commanded an altar or monument to be set up as a sign or memorial. God knows we need tangible reminders, but he was always specific that these be set up at his direction.
Serious problems arose when God’s people started setting things up on their own. In the time of the Judges, when everyone was doing what was right in their own eyes, one tribe set up their own idols and appointed their own priests. King Saul went terribly wrong when he set up a monument for himself. Many of the kings of Israel and Judah set up their own pillars and monuments. At times, the people even set up their own king."