JC

 The line you’re thinking of comes from the Bible, spoken by Jesus Christ during the Last Supper:

“And you are clean, though not every one of you.”

— Gospel of John 13:10

A closely related line appears just after:

“You are clean, but not all of you.”

— John 13:11

He was referring to his disciples, knowing that Judas Iscariot would betray him.