Charles Ellicott Commentary Mark 1:40-43

"And there cometh to him a leper, beseeching him, and kneeling down to him, and saying unto him, If thou wilt, thou canst make me clean. And being moved with compassion, he stretched forth his hand, and touched him, and saith unto him, I will; be thou made clean. And straightway the leprosy departed from him, and he was made clean. And he strictly charged him, and straightway sent him out," — Mark 1:40-43 (ASV)

And there came a leper.—See Notes on Matthew 8:1-4. The miracle appears in St. Matthew as following closely on the Sermon on the Mount.

He straitly charged him.—The word is the same as that in Matthew 9:30 (where see Note).