Luke 17: 5-10 Faith And Duty.
Normally we would see “disciples” asking questions, but here Luke is more specific, he says that the “apostles” said, “Increase our faith” (v. 5). However, Jesus taught that it is not the increase of faith that was important, because faith the size of a mustard seed, which is very small, can move a mulberry tree (v. 6). It is not the quantity of one’s faith but it’s quality. True faith evidences itself in humble duty, acknowledging that it is but the only legitimate response to the Lord’s commands (vv. 7-9). Faith shows itself in doing what the Lord has commanded (v. 10). The phrase “unprofitable servants” simply reinforces the point that no one brings anything to the work of salvation, including the exercise of faith. No one can repay the Lord (Rom. 11:35). Duty is simply the evidence of a God given faith.