John Gill Commentary Psalms 30:2

"O Jehovah my God, I cried unto thee, and thou hast healed me." — Psalms 30:2 (ASV)

O Lord my God, I cried unto thee
In the time of his distress and trouble; and whither should he go but unto his covenant God and Father?

and thou hast healed me :
either of some bodily disease that attended him; for the Lord is the physician of the body, as well as of the soul; and that either immediately, or by giving a blessing to means used; and the glory of such a mercy should be given to him.

Or else of soul diseases, which are natural and hereditary, epidemical, nauseous, mortal, and incurable, but by the grace of God and blood of Christ; and the healing: of them either respects the pardon of them at first conversion; for healing diseases, and forgiving iniquities, signify one and the same thing; or else fresh discoveries and applications of pardoning grace, after falls into sin, which are an healing backslidings, and restoring comforts; and this is God's work; none can heal but himself, and he does it effectually, universally, and freely, and which calls for thankfulness, (Psalms 103:1–3) ;

Or this may be understood in a civil sense, of restoring him to his house, his throne and kingdom, and the peace of it.