John 5:9

Consider now, I pray you, the exceeding wisdom of God. He raised not up the man at once, but first maketh him familiar by questioning, making way for the coming faith; nor doth He only raise, but biddeth him "take up his bed," so as to confirm the miracle that had been wrought, and that none might suppose what was done to be illusion or a piece of acting. For he would not, unless his limbs had been firmly and thoroughly compacted, have been able to carry his bed. And this Christ often doth, effectually silencing those who would fain be insolent. So in the case of the loaves, that no one might assert that the men had been merely satisfied, and that what was done was an illusion, He caused that there should be many relics of the loaves. So to the leper that was cleansed He said, "Go, show thyself to the priest" (Matt. viii. 4); at once providing most certain proof of the cleansing, and stopping the shameless mouths of those who asserted that He was legislating in opposition to God. This also He did in like manner in the case of the wine; for He did not merely show it to them, but also caused it to be borne to the governor of the feast, in order that one who knew nothing of what had been done, by his confession might bear to Him unsuspected testimony; wherefore the Evangelist saith, that the ruler of the feast "knew not whence it was," thus showing the impartiality of his testimony. And in another place, when He raised the dead, He said, "Give ye him to eat"; supplying this proof of a real resurrection, and by these means persuading even the foolish that He was no deceiver, no dealer in illusions, but that He had come for the salvation of the common nature of mankind.

But why did not Jesus require faith of this man, as He did in the case of others, saying, "Believest thou that I am able to do this?" It was because the man did not yet clearly know who He was; and it is not before, but after the working of miracles that He is seen so doing. For persons who had beheld His power exerted on others would reasonably have this said to them, while of those who had not yet learned who He was, but who were to know afterwards by means of signs, it is after the miracles that faith is required. And therefore Matthew doth not introduce Christ as having said this at the beginning of His miracles, but when He had healed many, to the two blind men only. Observe however in this way the faith of the paralytic. When he had heard, "Take up thy bed and walk," he did not mock, nor say, "What can this mean? An Angel cometh down and troubleth the water, and healeth only one, and dost Thou, a man, by a bare command and word hope to be able to do greater things than Angels? This is mere vanity, boasting, mockery." But he neither said nor imagined anything like this, but at once he heard and arose, and becoming whole, was not disobedient to Him that gave the command; for immediately he was made whole, and "took up his bed, and walked."