Psalm 52

"I am like a green olive tree in the house of God; I trust in the lovingkindness of God" (v8).  The person who trusts in God is contrasted with one who "would not make God his refuge, but trusted in the abundance of his riches" (v7).  Some people refuse to believe in what they can't see, and instead put their trust in themselves, their achievements, their profits, or other people.  They "love evil more than good" (v3) and reject God's mercy.

Real life (the green olive tree) is found in God.  His lovingkindness "endures all day long" (v1).