Mark 1:40

‘And there comes to him a leper, pleading with him and kneeling down to him, and saying to him, “If you will, you can make me clean.”

The disease would be some dreadful creeping skin disease, not necessarily strictly modern leprosy (see Leviticus 13:1), although such leprosy (Hansen's disease) was known in Palestine. All such diseases were so feared that the person was excluded from the community. People would shudder when they saw a skin diseased person, and scurry away. Such a person was forbidden to enter a dwelling place, and had to cry ‘Unclean' as a warning to others as he walked about (Leviticus 13:45). He was expected to keep away from people generally, and from any religious ritual observance, carrying out his religious obligations by means of others acting for him. He was excluded from the Temple. He was permanently ritually unclean. To touch him was to incur ritual uncleanness which had to be appropriately and lengthily dealt with. So he was excluded by man from society, and seen as religiously unacceptable.

Thus even his approach to Jesus put him in the wrong. He knew that he had no right to make such an approach, indeed was forbidden to do so. But understandably he was desperate. And he had heard wonderful things about this Man. So he approached Him and fell on his knees before Him. This was an acknowledgement that He saw Him as special, probably as ‘a man of God' filled with the power of God (2 Kings 1:13). No doubt by his action of humility he hoped to escape the rebuke that he deserved. But Mark probably intended his readers to see in his kneeling an indication of Who Jesus really is, the Son of God.

‘If you will, you can make me clean.' He has a God-given confidence that this Man can do the impossible. He is not expressing doubt about whether Jesus is willing to do it but confidence in what He can do. That is why he has plucked up his courage and come. It is a plea for help. Notice his desire, to be made ‘clean'. This is the thing above all that hurts him so deeply, not so much the dreadful disfigurement, but being unable to approach God's house and being unable to be in contact with fellow human beings.