LUKE 5 12 And it happened when He was in a certain city, that behold, a man who was full of leprosy saw Jesus; and he fell on his face and implored Him, saying, “Lord, if You are willing, You can make me clean.”13 Then He put out His hand and touched him, saying, “I am willing; be cleansed.” Immediately the leprosy left him. 14 And He charged him to tell no one, “But go and show yourself to the priest, and make an offering for your cleansing, as a testimony to them, just as Moses commanded.”15 However, the report went around concerning Him all the more; and great multitudes came together to hear, and to be healed by Him of their infirmities. 16 So He Himself often withdrew into the wilderness and prayed.17 Now it happened on a certain day, as He was teaching, that there were Pharisees and teachers of the law sitting by, who had come out of every town of Galilee, Judea, and Jerusalem. And the power of the Lord was present to heal them.

In falling upon his face he marked his humility and modesty, for every one should blush at the stains of his life, but his reverence kept not back his confession, he shews his wound, and asks for a remedy, saying, If thou wilt, thou canst make me clean. Of the will of the Lord he doubted, not from distrust of His mercy, but checked by the consciousness of his own unworthiness. But the confession is one full of devotion and faith, placing all power in the will of the Lord.

(St Ambropse)