Hebrews 10:32

32.But call to remembrance, etc. In order to stimulate them, and to rouse their alacrity to go forward, he reminds them of the evidences of piety which they had previously manifested; for it is a shameful thing to begin well, and to faint in the middle of our course, and still more shameful to retrograde after having made great progress. The remembrance then of past warfare, if it had been carried on faithfully and diligently under the banner of Christ, is at length useful to us, not as a pretext for sloth, as though we had already served our time, but to render us more active in finishing the remaining part of our course. For Christ has not enlisted us on this condition, that we should after a few years ask for a discharge like soldiers who have served their time, but that we should pursue our warfare even to the end.

He further strengthens his exhortation by saying, that they had already performed great exploits at a time when they were as yet new recruits: the more shame then would it be to them, if now they fainted after having been long tried; for the word enlightened is to be limited to the time when they first enlisted under Christ, as though he had said, “As soon as ye were initiated into the faith of Christ, ye underwent hard and arduous contests; now practice ought to have rendered you stronger, so as to become more courageous.” He, however, at the same time reminds them, that it was through God’s favor that they believed, and not through their own strength; they were enlightened when immersed in darkness and without eyes to see, except light from above had shone upon them. Whenever then those things which we have done or suffered for Christ come to our minds, let them be to us so many goads to stir us on to higher attainments. (191)