What Matthew Henry (1162-1714) said about Matthew 19:17:
'He [Jesus] tenderly assists his faith; for, doubtless, he did not mean it for a reproof, when he said, Why callest thou me good? But he would seem to find that faith in what he said, when he called him good Master, which the gentleman perhaps was not conscious to himself of; he intended no more than to own and honour him as a good man, but Christ would lead him to own and honour him as a good God; for there is none good but one, that is God. Note, As Christ is graciously ready to make the best that he can of what is said or done amiss; so he is ready to make the most that can be of what is well said and well done. His constructions are often better than our intentions; as in that, "I was hungry, and you gave me meat, though you little thought it was to me.'' Christ will have this young man either know him to be God, or not call him good; to teach us to transfer to God all the praise that is at any time given to us. Do any call us good? Let us tell them all goodness is from God, and therefore not to us, but to him give glory. All crowns must lie before his throne. Note, God only is good, and there is none essentially, originally, and unchangeably, good, but God only. His goodness is of and from himself, and all the goodness in the creature is from him; he is the Fountain of goodness, and whatever the streams are, all the springs are in him, Jam. 1:17. He is the great Pattern and Sample of goodness; by him all goodness is to be measured; that is good which is like him, and agreeable to his mind. We in our language call him God, because he is good. In this, as in other things, our Lord Jesus was the Brightness of his glory (and his goodness is his glory), and the express image of his person, and therefore fitly called good Master.
'(2.) He plainly directs his practice, in answer to his question. He started that thought of his being good, and therefore God, but did not stay upon it, lest he should seem to divert from, and so to drop, the main question, as many do in needless disputes and strifes of words. Now Christ's answer is, in short, this, If thou wilt enter into life, keep the commandments.'