Repenting tears are delicious.
They may be compared to myrrh, which though it is bitter in taste, has a sweet smell and refreshes the spirits. So repentance, though it is bitter in itself—yet it is sweet in the effects. It brings inward peace. The soul is never more enlarged and inwardly delighted—than when it can kindly melt. How oft do the saints fall aweeping for joy! The Hebrew word for “repent” signifies “to take comfort”. None so joyful as the penitent!
They say that tears have four qualities: they are hot, moist, salty, and bitter. It is true of repenting tears. They are hot, to warm a frozen conscience; moist, to soften a hard heart; salty, to season a soul putrefying in sin; bitter, to wean us from the love of the world. And I will add a fifth. They are sweet, in that they make the heart inwardly rejoice “Your sorrow shall be turned into joy!” (John 16:20). “Sorrowful, yet always rejoicing.” (2 Corinthians 6:10)
“Let a man,” said Augustine, “grieve for his sin and rejoice for his grief.” Tears are the best sweetmeats. David, who was the great weeper in Israel, was the sweet singer of Israel. The sorrows of the penitent are like the sorrows of a woman giving birth: “A woman giving birth to a child has pain because her time has come; but when her baby is born she forgets the anguish because of her joy that a child is born into the world” (John 16:21). So the sorrows of humbled sinners bring forth grace, and what joy there is when this child is born!
-Thomas Watson, The Doctrine of Repentance