10 For, lo, those “foolish virgins, who brought no oil with them,” wish to please men by that abstinence of theirs whereby they are called virgins, and by their good works, when they seem to carry lamps. And if they wish to please men, and on that account do all these praiseworthy works, they do not carry oil with them. Do you then carry it with you, carry it within where God sees; there carry the testimony of your conscience. For he who walks to gain the testimony of another, does not carry oil with him.
If you abstain from things unlawful, and do good works to be praised of men; there is no oil within. And so when men begin to leave off their praises, the lamps fail. Observe then, Beloved, before those virgins slept, it is not said that their lamps were extinguished. The lamps of the wise virgins burned with an inward oil, with the assurance of a good conscience, with an inner glory, with an inmost charity. Yet the lamps of the foolish virgins burned also. Why burnt they then?
Because there was yet no want of the praises of men. But after that they arose, that is in the resurrection from the dead, they began to trim their lamps, that is, began to prepare to render unto God an account of their works. And because there is then no one to praise, every man is wholly employed in his own cause, there is no one then who is not thinking of himself, therefore were there none to sell them oil; so their lamps began to fail, and the foolish betook themselves to the five wise, “give us of your oil, for our lamps are going out.” They sought for what they had been wont to seek for, to shine that is with others' oil, to walk after others' praises. “Give us of your oil, for our lamps are going out.”
Source: Sermons on Selected Lessons of the New Testament (New Advent)