What is the spiritual meaning of covering?

Accountability. When you have a group of seasoned, mature people, or a church overseeing you, you are covered by prayer and watchfulness so you are actually covered by the Lord according to His order. The Lord always had people or groups accountable for individuals. Some examples are Moses over the children of Israel, priests over the general public like Aaron, Jesus over the disciples, and Paul over those he was training. I hope this answers your intended question. Thanks.