John Chrysostom — as excerpted in the Catena Aurea on John 4:46-54

“(Hom. xxxv. 2) Or thus; In the centurion there was confirmed faith and true devotion, and therefore our Lord was ready to go. But the nobleman’s faith was still imperfect, as he thought our Lord could not heal in the absence of the sick person. But Christ’s answer enlightened him. And the man believed the word which Jesus had spoken to him, and went his way. He did not believe, however, wholly or completely.”