From Puritan Richard Baxter, Practical Works (London, 1830), 2:420-21:
Penitent sorrow is only a purge to cast out those corruptions which hinder you from relishing your spiritual delights. Use it therefore as physic [medicine], only when there is need; and not for itself, but only to this end; and turn it not into your ordinary food. Delight in God is the health of your souls. … So take up no sorrow against your delight in God, or instead of it, but for it, and so much as promoteth it.
(HT: Tony Reinke)