Persecuted - Often persecuted, persecuted in all places. The Book of Acts shows how true this was.
But not forsaken - Not deserted; nor left by God Though persecuted by people, yet they experi enced the fulfillment of the divine promise that he would never leave nor forsake them. God always interposed to aid them; always saved them from the power of their enemies; always sustained them in the time of persecution. It is still true. His people have been often persecuted. Yet God has often interposed to save them from the hands of their enemies; and where he has not saved them from their hands, and preserved their lives, yet he has never left them, but has sustained, upheld, and comforted them even in the dreadful agonies of death.
Cast down - Thrown down by our enemies, perhaps in allusion to the contests of wrestlers, or of gladiators.
But not destroyed - Not killed. They rose again; they recovered their strength; they were prepared for new conflicts. They surmounted every difficulty, and were ready to engage in new strifes, and to meet new trials and persecutions.

Persecuted, but not forsaken - Διωκομενοι, αλλ' ουκ εγκαταλειπομενοι. The διωκομενοι, pursued, is peculiar to the δρομος, or race, when one being foremost others pursue, and get up close after him, endeavoring to outstrip him, but cannot succeed: this is the meaning of ουκ εγκαταλειπομενοι, not outstripped, or outgone, as the word implies. So in Plutarch: τους απολειφθεντας ου στεφανουσι, they do not crown them that are distanced or left behind. So says the apostle, 1-Corinthians 9:24 : All run, but only One receiveth the Prize.
Cast down, but not destroyed - Καταβαλλομενοι αλλ' ουκ απολλυμενοι. This also belongs to wrestlers, where he that throws the other first is conqueror. And so Hesychius: καταβαλει, νικησει, ῥιψει, to cast down is to overcome, to throw. And then, the being not destroyed signifies that, although they were thrown down-cast into troubles and difficulties, yet they rose again, and surmounted them all.

Persecuted, but not forsaken,.... Pursued from place to place, and followed with menaces, curses, and reproaches; laid hold on, proscribed, imprisoned, and threatened with the severest tortures, and death itself; but our God never leaves us nor forsakes us; though we are followed close by evil men, and left by our friends, we are not forsaken of God:
cast down we sometimes are, as an earthen vessel; 2-Corinthians 4:7, which may be cast out of a man's hands, in order to be dashed to pieces; or as a man in wrestling, see Ephesians 6:12 may be thrown to the ground by his antagonist, so we are sometimes foiled by sin, Satan, and the world:
but not destroyed; we are still safe in the hands of Christ, and are kept by the power of God; and, indeed, to what else can all this be ascribed? it is surprising that earthen vessels should bear and suffer so much, and not fall, or be dashed to pieces.

not forsaken--by God and man. Jesus was forsaken by both; so much do His sufferings exceed those of His people (Matthew 27:46).
cast down--or "struck down"; not only "persecuted," that is, chased as a deer or bird (1-Samuel 26:20), but actually struck down as with a dart in the chase (Hebrews 11:35-38). The Greek "always" in this verse means, "throughout the whole time"; in 2-Corinthians 4:11 the Greek is different, and means, "at every time," "in every case when the occasion occurs."