If thou canst. Note how the Lord gives back the fathers question, with the same condition implied.
believe. Omitted by. Tr. [A] WH R; not by the Syriac all things. Figure of speech Synecdoche (App-6). All things included in the promise.
Related Commentaries of Mark 9:23
Mark 9:23
23 Jesus said unto him,If thou canst believe, all things are possible to him that believeth.