Matthew 17:19

Τότε προσελθόντες οἱ μαθηταὶ τῷ Ἰησοῦ κατ᾽ ἰδίαν εἶπον, Διὰ τί ἡμεῖς οὐκ ἠδυνήθημεν ἐκβαλεῖν αὐτό;

RBT Translation:

At that time the Learners, those who have drawn near to the Salvation according to his own, said "For what reason were we not able to cast out self?"

Julia Smith Literal 1876 Translation:
Then the disciples having come to Jesus apart, said, Why could not we cast it out?

LITV Translation:
Then coming up to Jesus privately, the disciples said, Why were we not able to cast him out?