Lateran Council IV, 1215

one can accomplish this sacrament except a priest who has been rightly ordained according to the keys of the Church which Jesus Christ Himself conceded to the Apostles and to their successors. But the sacrament of baptism (which at the invocation of God and the indivisible Trinity, namely, of the Father and of the Son and of the Holy Spirit, is solemnized in water) rightly conferred by anyone in the form of the Church is useful unto salvation for little ones and for adults. And if, after the reception of baptism, anyone shall have lapsed into sin, through true penance he can always be restored. Moreover, not only virgins and the continent but also married persons pleasing to God through right faith and good work merit to arrive at a blessed eternity.

Chap. 2. The Error of Abbot Joachim ¹

431. We condemn, therefore, and we disapprove of the treatise or tract which Abbot Joachim published against Master Peter Lombard on the unity or essence of the Trinity, calling him heretical and senseless because in his Sentences he said: "Since it is a most excellent reality—the Father, and the Son, and the Holy Spirit, and it is not generating, nor generated, nor proceeding." ² Thus he (Joachim) declares that Peter Lombard implies not so much a Trinity as a quaternity in God, namely the three Persons and that common essence as a fourth, openly protesting that there is no matter which is the Father and the Son and the Holy Spirit; neither is there essence, nor substance, nor nature, although he concedes that the Father, and the Son, and the Holy Spirit are one essence, one substance, and one nature. But he says that unity of this kind is not true and proper, but is something collective and similar, as many men are called one people, and many faithful, one Church, according to the following: "Of the multitude believing there was one heart and one mind" [Acts 4:32]; and, "He who clings to God is one spirit with him" [I Cor. 6:17]; likewise, "He who . . . plants and he who waters are one" [I Cor. 3:8]; and, "we are all one body in Christ" [Rom. 12:5]; again in the Book of Kings [Ruth]: "My people and your people are one" [Ruth 1:16]. Moreover, to add to this opinion of his he brings the following most powerful expression, that Christ spoke in the Gospel about the faithful: "I will, Father, that they are one in us as we are one, so that they may be perfected in unity" [John 17:22 f.]. For not, (as he says), are the faithful of Christ one, that is, a certain one matter which is common to all, but in this way are they one, that is, one Church because of the unity of the Catholic faith; and finally one kingdom, because of the union of indissoluble love, as in the canonical letter of John the Apostle we read: "For there are three that give testimony in heaven, the