Mark 1:40

And there came a leper to him
After he was come down from a certain mountain, in Galilee, where he had been preaching to the people, ( Matthew 8:1 ) , and when be was in a certain city, ( Luke 5:12 ) , either Capernaum, or some other city of Galilee. This man was full of leprosy, as Luke says, and very probably deemed incurable; of the nature and symptoms of the leprosy, (See Gill on Luke 5:12),

beseeching him;
to cure him of his leprosy:

and kneeling down to him;
in token of submission, respect, and reverence, and to worship him:

and saying unto him, if thou wilt thou canst make me clean;
(See Gill on Matthew 8:2). Mark omits the word "Lord".