23 But what do you say? “Behold, we suffer many evils.” Would that you suffered these for Christ, not for your own honor! Hear what follows: They, indeed, boast sometimes, because they do many alms, give to the poor; because they suffer afflictions: but it is for Donatus, not for Christ. Consider how you suffer, for if you suffer for Donatus, it is for a proud man: you are not in the dove if you are suffering for Donatus. Donatus was not the friend of the Bridegroom; for had he been, he would have sought the glory of the Bridegroom, not his own.
See the friend of the Bridegroom saying, “This is He that baptizes.” He, for whom you are suffering, was not the friend of the Bridegroom. You have not the wedding garment; and if you have come to the feast, you will be put out of doors; nay, you have been cast out of doors already, and for that reason you are wretched: return at length, and do not boast. Hear what the apostle says: “Though I should distribute all my goods to the poor, and give my body to be burnt, but have not charity.”
See what you do not have. “Though,” he says, “I should give my body to be burnt;” and that, too, for the name of Christ; but since there are many who do this boastfully, not with charity, therefore, “Though I should give my body to be burnt, and have not charity, it profits me nothing.” It was by charity those martyrs, who suffered in time of persecution, did this; but these men do it of their vanity and pride; for in the absence of a persecutor, they throw themselves headlong into destruction. Come, then, that you may have charity. “But we have our martyrs.” What martyrs? They are not doves; hence they attempted to fly, and fell over the rock.
Source: Tractates on the Gospel of John (New Advent)