1 Grk “And behold, a leper came.” The Greek word ἰδού (idou) has not been translated because it has no exact English equivalent here, but adds interest and emphasis ( 1). The ancient term for leprosy covers a wider array of conditions than what we call leprosy today. A leper was totally ostracized from society until he was declared cured (Lev 13:45–46).
2 Grk “a leper approaching, bowed low before him, saying.”
3 This is a third class condition. The report portrays the leper making no presumptions about whether Jesus will heal him or not.

In other versions

And behold, a leper came to him and knelt before him, saying, “Lord, if you will, you can make me clean.”

A man with leprosy came and knelt before him and said, “Lord, if you are willing, you can make me clean.”

Right away a man with leprosy came up and knelt before him, saying, “Lord, if you are willing, you can make me clean.”

Suddenly, a man with leprosy approached him and knelt before him. “Lord,” the man said, “if you are willing, you can heal me and make me clean.”

And behold, a leper approached and worshiped him, saying, “Lord, if you are willing, you are able to make me clean.”

And, behold, there came a leper and worshipped him, saying, Lord, if thou wilt, thou canst make me clean.

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