This Psalm was written by Asaph the Levite. Responsible for the execution of the outward rituals of sacrifice, he was there and observed the people as they went through the routines of atoning for their sins. He notices that even though their actions were the same, their hearts and attitudes were not.
Asaph describes in this Psalm the difference between true and false religion. False religion trusts in the rituals with no inward change. True religion trusts in God and the rituals of their religion are motivated by their relationship with Him.
In true religion, rituals serve the relationship.