ثُمَّ صَدَقْنَـٰهُمُ ٱلْوَعْدَ فَأَنجَيْنَـٰهُمْ وَمَن نَّشَآءُ وَأَهْلَكْنَا ٱلْمُسْرِفِينَ
summa sadaqnaa humul wa'da fa-anjainaahum wa man nashaaa'u wa ahlaknal musrifeen
Then we made good our promise to them: we delivered them and whomever we willed, and we destroyed those who went beyond all bounds.
The promise kept is rescue within history, since the preceding verse has already said plainly that these messengers ate food and died. Ṣadaqnāhum is a verb of being true to someone in a promise, taking the promise itself as its object, and it appears just this once. Those delivered include others besides the messengers, left unnamed, so the rescue reaches wider than the men who carried the message.