Theophylact of Ohrid
Catena Aurea · Lukasevangelium 17
Lk 17, Verses 5–6English original
And the apostles said unto the Lord, Increase our faith. And the Lord said, If ye had faith as a grain of mustard seed, ye might say unto this sycamine tree, Be thou plucked up by the root, and be thou planted in the sea; and it should obey you.
The disciples hearing our Lord discoursing of certain arduous duties, such as poverty, and avoiding offences, entreat Him to increase their faith, that so they might be able to follow poverty, (for nothing so prompts to a life of poverty as faith and hope in the Lord,) and through faith to guard against giving offences. Therefore it is said, And the Apostles said unto the Lord, Increase our faith.