Remember what He asked for, and you will plainly see that he doubted. He asked Him to come down and see his son: The nobleman saith unto him, Sir, come down, ere my child die. His faith was deficient; in that he thought that our Lord could not save, except He were personally present.
Reproduced in full. Translation: Oxford 1841 (Newman), public domain (Public domain).
Also cites: Hom. in Evang. xxviii. 1