John Gill Bible Commentary

When his disciples heard it..... That is, the difficulty of a rich man's entering into the kingdom of heaven, aggravated by the above proverbial expression, they were exceedingly amazed. They were surprised at his first words; but when he confirmed them by the proverb of a camel's passing through the eye of a needle, they were, as Mark says, "astonished out of measure": they did not imagine there was any difficulty of rich men coming into the kingdom of the Messiah, which they took to be a worldly one, and would be filled with rich men; for so they understood Christ; though he meant by the kingdom of heaven a spiritual kingdom, a Gospel church state here, or the heavenly glory, or both; but when he expressed, by the proverb, the impracticableness of such men becoming the subjects thereof, their amazement increased; saying, as in Mark, "among themselves", privately to one another, who then can be saved? meaning, not with a spiritual and everlasting salvation, but a temporal one: for upon Christ's so saying, they might reason with themselves, that if rich men did not come into the kingdom of the Messiah, they would oppose him and his kingdom, with all their force and strength; and then what would become of such poor men as themselves, who would not be able to stand against them? nor could they hope to be safe long, or enjoy any continued happiness in the expected kingdom, should this be the case.