Blessing in the new dispensation would not be on the principle of works to merit favour with God (as was the case under the Law), but on the principle of free grace (Rom. 4:4-5). This is illustrated in the difference between the manner in which blessing was available to those at the pool of "Bethesda" and the manner in which blessing came to "the impotent man" who was healed by the Lord.
The scene at the pool is a picture of the legal system in the old dispensation (vss. 1-4). The pool had "five porches" which figuratively speak of the five books of Moses. At certain times, an angel would come down and trouble the water, and the person who got down over the five porches and into the pool first, got the blessing. Blessing was there, but it was conditioned upon having to do something to get it. It illustrates the works-based system of the Law, which said to all who came to it for blessing, "This do, and thou shalt live" (Luke 10:28). A person had to keep something like 613 injunctions from the five books of Moses, and if he did, he would get the blessing.
In contrast to this, with the coming of the Son of God (His first advent), the blessings of grace would be granted to all who would receive His Word, without legal doing (Rom. 4:4-5; 11:6; Eph. 2:9; Titus 3:5). This is illustrated in the impotent man being blessed without having to climb over the five porches and get into the pool (vss. 5-16). For many years this man had been struggling to obtain blessing from the pool, and he couldn't get it; with the coming of the Son of God he didn't need it! It points to the fact that in the new dispensation there would be a cessation of law-keeping. "Christ is the end of the law for righteousness to everyone that believeth" (Rom. 10:4).
It is significant that this miracle was done on the Sabbath day, which the Pharisees thought was a violation of that day. It suggests that grace cannot be confined to the legal system, and that the Sabbath would no longer be observed in the Dispensation of Grace. Christ is the "Lord even of the Sabbath day" (Matt. 12:8) and therefore, greater than the Sabbath. He had the power to work for the blessing of man on that day as He did on every day.