Правило 5 Василия Великого

Heretics, upon the death of repentants, should be received. It is obvious that they accept it not without reasoning, but with testing, whether they show true repentance, and whether they have fruits that testify to their care for salvation. (I Om. 2, 14; II Om. 7; Trul. 78, 96; Neokes. 12; Laod. 19, 47; Carth. 45). Heretics who convert to Orthodoxy must be received, according to the rules, according to the rank established for various groups of heretics (II Ecumenical 7). And this must be done all the more quickly if heretics who want to be saved are on the verge of death. Saint Basil also speaks about this in the present rule, adding that it is necessary to test whether the subject person really and sincerely condemns the heresy that he previously professed, and whether he will remain firm in confessing the Orthodox faith if he remains alive; otherwise, the heretic should not be honored with St. communion and at death. You might be interested in: