We view those Christians that lived in the first hundred years to be Christian, Catholics as Catholics. Lets be honest ---- the Church of 33AD was different than the Church of 353 AD and much different than 1563.
Not really.
They believed the same things.
Clearly, the Church was able to be more open and actually build buildings after Christianity was legal, but the beliefs were the same:
“And thus preaching through countries and cities, they appointed the first-fruits [of their labours], having first proved them by the Spirit, to be bishops and deacons of those who should afterwards believe. Nor was this any new thing, since indeed many ages before it was written concerning bishops and deacons. For thus saith the Scripture a certain place, ‘I will appoint their bishops s in righteousness, and their deacons in faith.’… Our apostles also knew, through our Lord Jesus Christ, and there would be strife on account of the office of the episcopate. For this reason, therefore, inasmuch as they had obtained a perfect fore-knowledge of this, they appointed those [ministers] already mentioned, and afterwards gave instructions, that when these should fall asleep, other approved men should succeed them in their ministry…For our sin will not be small, if we eject from the episcopate those who have blamelessly and holily fulfilled its duties.” Pope Clement, Epistle to Corinthians, 42, 44 (A.D. 98).
“For what is the bishop but one who beyond all others possesses all power and authority, so far as it is possible for a man to possess it, who according to his ability has been made an imitator of the Christ off God? And what is the presbytery but a sacred assembly, the counselors and assessors of the bishop? And what are the deacons but imitators of the angelic powers, fulfilling a pure and blameless ministry unto him, as…Anencletus and Clement to Peter?” Ignatius, To the Trallians, 7 (A.D. 110).
“Hegesippus in the five books of Memoirs which have come down to us has left a most complete record of his own views. In them he states that on a journey to Rome he met a great many bishops, and that he received the same doctrine from all. It is fitting to hear what he says after making some remarks about the epistle of Clement to the Corinthians. His words are as follows: ‘And the church of Corinth continued in the true faith until Primus was bishop in Corinth. I conversed with them on my way to Rome, and abode with the Corinthians many days, during which we were mutually refreshed in the true doctrine. And when I had come to Rome I remained a there until Anicetus, whose deacon was Eleutherus. And Anicetus was succeeded by Soter, and he by Eleutherus. In every succession, and in every city that is held which is preached by the law and the prophets and the Lord.’” Hegesippus, Memoirs, fragment in Eusebius Ecclesiatical History, 4:22 (A.D. 180).