After preaching the Sermon on the Mount (Matthew 5-7), Jesus came down the hillside followed by a large crowd. A leper approached Jesus and was miraculously healed of his skin disease.
As described in the book of Luke, which is in the New Testament of the Bible:
12 While he was in one of the cities, behold, there was a man full of leprosy. When he saw Jesus, he fell on his face and begged him, saying, “Lord, if you want to, you can make me clean.”
13 He stretched out his hand and touched him, saying, “I want to. Be made clean.”
Immediately the leprosy left him. 14 He commanded him to tell no one, “But go your way and show yourself to the priest, and offer for your cleansing according to what Moses commanded, for a testimony to them.”
15 But the report concerning him spread much more, and great multitudes came together to hear and to be healed by him of their infirmities. (Luke 5:12-15, WEB)
Note: The word "leprosy" can refer to a variety of diseases that affect a person's skin.
Read more in the book Jesus the Miracle Worker: The 50 miracles of Jesus explained in chronological order (The Jesus Series) -- now available at amazon.
Next: 9. Healing a paralyzed man (Matthew 9:1-8, Mark 2:1-12, Luke 5:18-26)