A passage quoted by the heretics against repentance is explained in two ways, the first being that Hebrews 6:4 refers to the impossibility of being baptized again; the second, that what is impossible with man is possible with God.
6. Being then refuted by the clear example of the Apostle and by his writings, the heretics yet endeavour to resist further, and say that their opinion is supported by apostolic authority, bringing forward the passage in the Epistle to the Hebrews: For it is impossible that those who were once enlightened, and have tasted the heavenly gift, and have been made partakers of the Holy Spirit, and have tasted the good word of God, and the powers of the world to come, should if they fall away be again renewed unto repentance, crucifying again the Son of God, and put Him to open shame.
7. Could Paul teach in opposition to his own act? He had at Corinth forgiven sin through penance, how could he himself speak against his own decision? Since, then, he could not destroy what he had built, we must assume that what he says was different from, but not contrary to, what had gone before. For what is contrary is opposed to itself, what is different has ordinarily another meaning. Things which are contrary are not such that one can support the other. Inasmuch, then, as the Apostle spoke of remitting penance, he could not be silent as to those who thought that baptism was to be repeated. And it was right first of all to remove our anxiety, and to let us know that even after baptism, if any sinned their sins could be forgiven them, lest a false belief in a reiterated baptism should lead astray those who were destitute of all hope of forgiveness. And secondly, it was right to set forth in a well-reasoned argument that baptism is not to be repeated.
8. And that the writer was speaking of baptism is evident from the very words in which it is stated that it is impossible to renew unto repentance those who were fallen, inasmuch as we are renewed by means of the laver of baptism, whereby we are born again, as Paul says himself: For we are buried with Him through baptism into death, that, like as Christ rose from the dead through the glory of the Father, so we, too, should walk in newness of life. Romans 6:4 And in another place: Be renewed in the spirit of your mind, and put on the new man which is created after God. Ephesians 4:23 And elsewhere again: Your youth shall be renewed like the eagle, because the eagle after death is born again from its ashes, as we being dead in sin are through the Sacrament of Baptism born again to God, and created anew. So, then, here as elsewhere, he teaches one baptism. One faith, he says, one baptism. Ephesians 4:5
