If you can’t find it in the Bible, you don’t need to do it to have salvation.”
Seriously, Hose, who told you that? There wasn’t even a Canon of the NT until after 300.
Canon isn't the issue; SCRIPTURE has been in existence since the Holy Spirit lead those to write what he inspired in them. You know... Paul's Letters, Gospels, etc.
In answer to your query, however, Scripture tells us this (and since Scripture is the inspired, inerrant word of God, God is the one who "told" me):
2 Timothy 3:14-17
"[14] But as for you, continue in what you have learned and have firmly believed, knowing from whom you learned it [15] and how from childhood you have been acquainted with the sacred writings, which are able to make you wise for salvation through faith in Christ Jesus. [16] All Scripture is breathed out by God and profitable for teaching, for reproof, for correction, and for training in righteousness, [17] that the man of God may be complete, equipped for every good work."
emphasis mine.
So.... it appears to me that this was in existence FAR before the EO or RCC came about. And God-breathed. So, if you have an issue with what's in the Bible, take it up with God -- he's the author. I can't help it if RCCs and EOs add thing required for salvation that God didn't require; I can't help it if those churches teach a false gospel and heresy.
Hoss
Stop tossing out partial truths. In Polycarp’s letter to the Philipians he quotes from or alludes to passages from all 27 of what became our New Testament.