'Built an Altar' in the Bible

Then Joshua built an altar for the Lord God of Israel on Mount Ebal,

The Israelites received this report: "Look, the Reubenites, Gadites, and half-tribe of Manasseh have built an altar at the entrance to the land of Canaan, at Geliloth near the Jordan on the Israelite side."

"The entire community of the Lord says, 'Why have you disobeyed the God of Israel by turning back today from following the Lord? You built an altar for yourselves and have rebelled today against the Lord.

If we have built an altar for ourselves to turn back from following the Lord by making burnt sacrifices and grain offerings on it, or by offering tokens of peace on it, the Lord himself will punish us.