When Jesus healed the sick, he instructed them not to publish it. Why do some centres publish these healing incidents?
Jesus was no wonder-worker. His miracles were symbols or signs of His salvific act. He worked them for the greater glory of God (Jn. 11.4). The right reaction of a multitude witnessing a miracle or a person who has experienced God's miraculous power, is glorification of God (Mt.31). When Jesus forbids the beneficiary not to reveal the miracle, Jesus is taking caution that he is not misunderstood as a wonder-worker (Jn. 6:26), that his Messiahship (Mt. 16:16) is kept secret until his followers could accept it with all its implications and demands (Mt. 16:21-23). Further He wanted people to glorify God, His Father who is working through Him. .
After cleansing the leper, Jesus said to him "see that you say nothing to anyone, but go your way, show yourself to the priest and offer for your cleansing" (Mk.1 :44). After doing that (glorifying God), however, he went and proclaimed what Jesus had done to him (V. 45). After healing a man possessed by demon, Jesus did not permit him to remain with Him, but said to him, "Go home to your friends, and tell what great things the Lord has done for you, and how He had compassion on you" (Mk. 5:19). He departed, and probably after going to his friends and praising the Lord, he began to proclaim in Decapolis, all that Jesus had done for him, and all marveled" (V. 20). Hence, after glorifying God, and for glorifying God, one may proclaim the miracles done to him by Jesus. "Let your light so shine before men, that they may see your good works and glorify your Father in Heaven" (Mt. 5:16; In. 15:8). Even the witness of a Samaritan woman could lead many to believe in Jesus (Jn. 4:39). However, each person has to believe in Jesus, experiencing on his own, that Christ is the Saviour of the World. (Cf. V. 42).