God's letter/epistle, to us, written by the Apostle Paul assures us of God's love by way of mercy comfort and consolation. Which means we have these words to speak to ourself in time of tribulation and trouble.  Plus, the truth that all God's promises are all good and only good.  So, we, born-again ones then rejoice in the joy God has given us.  We do have joy in us.  It is the second fruit of the spirit.  So, let us use it with love (first fruit)and thanksgiving, walking in Jesus Christ's victory, glorifying God.

i cor 1.20