Theophylact of Ohrid — as excerpted in the Catena Aurea on Luke 17:11-19

“They therefore stand afar off as if ashamed of the uncleanness which was imputed to them, thinking that Christ would loathe them as others did. Thus they stood afar off, but were made nigh unto Him by their prayers. For the Lord is nigh unto all them that call upon him in truth. (Ps. 145:18.) Therefore it follows, And they lifted up their voices, and said, Jesus, Master, have mercy upon us.”