The persuasive power with which Irenaeus set up the principle of the apostolic "rule of truth," or of "tradition" or simply of "faith," was undoubtedly, as far as he himself was concerned, based on the facts that he had already a rigidly formulated creed before him and that he had no doubt as to its interpretation.[37] The rule of truth (also [Greek: he hypo tes ekklesias keryssomene aletheia] "the truth proclaimed by the Church;" and [Greek: to tes aletheias somation], "the body of the truth") is the old baptismal confession well known to the communities for which he immediately writes. (See I. 9. 4; [Greek: houto de kai ho ton kanona tes aletheias akline en heauto katechon hon dia tou baptismatos eilephe], "in like manner he also who retains immovably in his heart the rule of truth which he received through baptism"); because it is this, it is apostolic, firm and immovable.[38] By the fixing of the rule of truth, the formulation of which in the case of Irenaeus (I. 10. 1, 2) naturally follows the arrangement of the (Roman) baptismal confession, the most important Gnostic theses were at once set aside and their antitheses established as apostolic. In his apostolic rule of truth Irenaeus himself already gave prominence to the following doctrines:[39] the unity of God, the identity of the supreme God with the Creator; the identity of the supreme God with the God of the Old Testament; the unity of Jesus Christ as the Son of the God who created the world; the essential divinity of Christ; the incarnation of the Son of God; the prediction of the entire history of Jesus through the Holy Spirit in the Old Testament; the reality of that history; the bodily reception ([Greek: ensarkos analepsis]) of Christ into heaven; the visible return of Christ; the resurrection of all flesh ([Greek: anastasis pases sarkos, pases anthropotetos]), the universal judgment. These dogmas, the antitheses of the Gnostic regulae,[40] were consequently, as apostolic and therefore also as Catholic, removed beyond all discussion.