John Gill Bible Commentary

Then Peter began to say unto him,.... only observing that Christ promised treasure in heaven to the young man, provided he sold all that he had, and gave it to the poor; but being, in some measure, freed from that surprise and astonishment, which had seized him, and his fellow disciples, at the representation of the difficulty of a rich man's entering into the kingdom of God, by the last words; and taking heart from thence, began to take notice of the following case, as an instance and illustration of what Christ had said; for that same power, which had caused them to quit all their worldly substance for Christ, though it was but small, could also work a like effect upon the heart of a man ever so rich: lo! we have left all, and have followed thee: in Matthew it is added, "what shall we have therefore?" See Gill on Mat 19:27.