It can be found in ACTS 15.
Surely it is the nub of all Catholic teachings.
And those seven churches mentioned by the angel in Revelation were ALL Catholic ones as well.
They are fine examples of how well Catholic teachers got the theology right.
Except that Peter et al. was not Catholic. The classic evangelical gospel itself that he preached in Acts 10 and referred to in 15 was that of penitent, heart-purifying, regenerating effectual faith - before baptism but shown in it. (Acts 10:43-47; 15:7-9) And which is interpretive of Acts 2:38, in which, since belief is synonymous with obedience, then to call souls to do what faith examples is to call them to believe. (Likewise "Whether is it easier to say to the sick of the palsy, Thy sins be forgiven thee; or to say, Arise, and take up thy bed, and walk?" (Mark 2:9) Meaning since the cause and effect go together, then they can be used interchangeably, but the effect is not to be confused as being the cause.)
To him give all the prophets witness, that through his name whosoever believeth in him shall receive remission of sins...Then answered Peter, Can any man forbid water, that these should not be baptized, which have received the Holy Ghost as well as we? (Acts 10:43,47)
And when there had been much disputing, Peter rose up, and said unto them, Men and brethren, ye know how that a good while ago God made choice among us, that the Gentiles by my mouth should hear the word of the gospel, and believe. And God, which knoweth the hearts, bare them witness, giving them the Holy Ghost, even as he did unto us; And put no difference between us and them, purifying their hearts by faith. (Acts 15:7-9)
And it is that faith which is imputed for righteousness, (Romans 4:5) and is shown following the Lord, (Acts 2:38-47; Jn. 10:27,28) By which faith the redeemed soul is "accepted in the Beloved and seated with their Lord in Heaven, and have boldness to enter into the holy of holies, (Eph. 1:6; 2:6; Heb. 10:19; cf. Phil. 3:21) and will go to be with the Lord at death or at His return. . (Lk. 23:43 [cf. 2Cor. 12:4; Rv. 2:7]; Phil 1:23; 2Cor. 5:8 [“we”]; 1Cor. 15:51ff'; 1Thess. 4:17) Note in the latter case all believers were assured that if the Lord returned, which they expected in their lifetime, so would they “ever be with the Lord.” (1Thes. 4:17) though they were still undergoing growth in grace, as was Paul, who expressed he would go to be with the Lord at death, yet was not already perfect. (Phil. 3:10f)
And with the only suffering for believers that is manifestly taught as after this life being that of the judgment seat of Christ, which does not begin at death, but awaits the Lord's return, (1 Corinthians 4:5; 2 Timothy. 4:1,8; Revelation 11:18; Matthew 25:31-46; 1 Peter 1:7; 5:4) and is the suffering of the loss of rewards (and the Lord's displeasure) due to the manner of material one built the church with, which one is saved despite the loss of such, not because of. (1 Corinthians 3:8ff)
Meanwhile it was a actually Catholic council that elected pope Francis, as well as affirmed distinctive Catholic teachings that are not manifest in the only wholly inspired substantive authoritative record of what the NT church believed. However, the principle of councils of mature men to settle matters is Scriptural, and should be the ideal.
" It belongs to synods and councils, ministerially to determine controversies of faith, and cases of conscience; to set down rules and directions for the better ordering of the public worship of God, and government of his Church; to receive complaints in cases of maladministration, and authoritatively to determine the same; which decrees and determinations, if consonant to the Word of God, are to be received with reverence and submission; not only for their agreement with the Word, but also for the power whereby they are made, as being an ordinance of God appointed thereunto in His Word." - Westminster Confession XXXI)