Catholics have always labeled Protestants as heretics for their willful separation from the “true” church. But this accusation applies rather to them. They are the ones who interposed a priestly hierarchy between Christ and man and made to non-effect two of the commandments of God by substituting man-inspired tradition for God inspired commandments.
Jesus spoke to the "priestly authorities " of His day and accused them of voiding the commandments of God by their man-made traditions (See Mark 15:9) And Paul warned:
Col 2:8 Beware lest any man spoil you through philosophy and vain deceit, after the tradition of men, after the rudiments of the world, and not after Christ.
Catholics claim their authority from Peter supposing that he was designated as head of the early church. But the New Testament gave no one apostle priestly authority over other apostles, and Peter himself said all believers were as priests :
1 Pet 2:5 Ye also, as lively stones, are built up a spiritual house, an holy priesthood, to offer up spiritual sacrifices, acceptable to God by Jesus Christ.
1 Pet 2:9 But ye [are] a chosen generation, a royal priesthood, an holy nation, a peculiar people; that ye should show forth the praises of him who hath called you out of darkness into his marvellous light:
Catholicism made the Pope ( by tradition only and without Divine authority), the Vicar of Christ on Earth, and his subjects even began to call him “Your Holiness” and bow down and kiss his ring, but Jesus said:
Matt 23:8 But be not ye called Rabbi: for one is your Master, [even] Christ; and all ye are brethren.
23:9 And call no [man] your father upon the earth: for one is your Father, which is in heaven.
23:10 Neither be ye called masters: for one is your Master, [even] Christ.
23:11 But he that is greatest among you shall be your servant.
23:12 And whosoever shall exalt himself shall be abased; and he that shall humble himself shall be exalted.
When Cornelius bowed down to Peter, Peter was horrified ;
Acts 10:25 And as Peter was coming in, Cornelius met him, and fell down at his feet, and worshipped [him]. 10:26 But Peter took him up, saying, Stand up; I myself also am a man.
What would Peter think today if he saw all the bowing and scraping church members perform in the presence of the priests and the Pope?
The Bible says that the saints are those that have the faith of Jesus and keep the commandments of God. (Rev 14:12)
Jesus said in Luke 11:28 “Yea rather, blessed [are] they that hear the word of God, and keep it”
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Paul said inRom 8:9 But ye are not in the flesh, but in the Spirit, if so be that the Spirit of God dwell in you. Now if any man have not the Spirit of Christ, he is none of his."
So it is those who hear the word of God , allow His spirit to dwell in them and keep His commandments who are His church. In speaking of the Catholic church’s errors in interposing the church hierarchy between Christ and man which led to the Reformation, historian, Merle D’Aubigne said
" Originally, whoever possessed the spirit of Jesus Christ was a member of the Church; now the terms were inverted, and it was maintained that he only who was a member of the Church could receive the Spirit."
As these ideas became established, the distinction between the people and the clergy was more strongly marked. The salvation of souls no longer depended entirely on faith in Christ, but also, and in a more especial manner, on union with the Church. The representatives and heads of the Church were made partakers of the trust that should be placed in Christ alone.
Sola Scriptura is our safeguard against tradition and doctrine which countermands the word of God.
Isaiah said it best:"To the law and to the testimony: if they speak not according to this word, [it is] because [there is] no light in them. Isa 8:20
The Protest at Speyer, Germany 1529.reaffirmed sola scriptura as stated in Isaiah 8:20, Quote:
“” that there is no sure doctrine but such as is conformable to the word of God; that the Lord forbids the teaching of any other doctrine; that each text of the holy Scriptures ought to be explained by other and clearer texts; that this holy book is in all things necessary for the Christian, easy of understanding, and calculated to scatter the darkness: we are resolved, with the grace of God, to maintain the pure and exclusive preaching of his only word, such as it is contained in the biblical books of the Old and New Testament, without adding anything thereto that may be contrary to it. * This word is the only truth; it is the sure rule of all doctrine and of all life, and can never fail or deceive us. He who builds on this foundation shall stand against all the powers of hell, while all the human vanities that are set up against it shall fall before the face of God." Protestant Protest at Speyer , Germany 1529.