Jamieson, Fausset and Brown on 2 Corinthians 6:5

imprisonments--(2Co 11:23). He had been, doubtless, elsewhere imprisoned besides at Philippi when he wrote this Epistle.

tumults--(Ac 13:50; 14:5, 19; 16:22; and recently Ac 19:23-41).

labours--in the cause of Christ (2Co 11:23; Ro 16:12).

watchings--(2Co 11:27). Sleepless nights.

fastings--The context here refers to his trials, rather than devotional exercises (compare 2Co 11:27). Thus "foodlessness" would seem to be the sense (compare 1Co 4:11; Php 4:12). But the usual sense of the Greek is fasts, in the strict sense; and in 2Co 11:27 it is spoken of independently of "hunger and thirst." (Compare Lu 2:37; Ac 10:30; 14:23). However, Mt 15:32; Mr 8:3, justify the sense, more favored by the context, foodlessness, though a rare use of the word. Gaussen remarks "The apostles combine the highest offices with the humblest exterior: as everything in the Church was to be cast in the mould of death and resurrection, the cardinal principle throughout Christianity."