Rest is an activity!
Psalm 37 has nine imperatives. This is one of them. Please recall before reading this: an imperative sentence has an understood subject (you).
“Rest in the Lord. . .” which is a resting while working kind of rest. It is not a rocking chair kind of rest. It is more like sitting in the shade breaking beans. This rest means waiting for direction in a peaceful manner. This kind of rest is found in Proverbs 4:8 which describes the trusting soul as one who lies down in peace and sleeps. It is Peter, in Acts 12, sleeping in a quad of guards awaiting court the following morning. Jesus rested in sound sleep while the winds howled around him and threatened to sink the ship. We must remember that Jesus calms our storms, fears, and anxious moments. Rest, and wait.
This is a little sliver of the Bible study lessons I have on Psalm 37. I developed the lessons three years ago and brought them back out last week to use. Sometimes I look at what I have written in the past with surprise!