See on Mat 4:23; and Mar 3:10. Marking the two classes of disease recognized in medical writings, chronic and acute.
Evil spirits (πνευμάτων πονηρῶν)
On πονηρός, evil, see Luk 3:19. It is applied to evil spirits by Luke only, with the single exception of Mat 12:45. In accordance with its signification of evil on its active side, it is applied in medicine to that which spreads destruction or corruption; as the poison of serpents. Note, moreover, that Luke distinguishes here between disease and demoniac possession, as often. See Luk 6:17, Luk 6:18; Luk 8:2; Luk 13:32.
He gave (ἐχαρίσατο)
More is expressed by this verb than simple giving. He gave as a free, gracious, joy-giving gift. See on χάρις, favor, Luk 1:30; and compare freely give, Rom 8:32. Also, 1Co 2:12.