Christians must be cheerful in order to be useful. Hence, “rejoice in the Lord always,” is one of the commandments of the Decalogue of grace. A morose Christian will restrain his blessing from the world.
O, unhappy disciples, “the joy of the Lord is your strength,” and you will be weak and of little use till you find that joy.
“And these things write we unto you that your joy may be full” (1 John 1:4).