Well let's go to neutral ground for a mere moment without going in the weeds. I have seen Roman Catholics cite the Didache to show church traditions in practice.
Didache on the Lord's Supper
Didache 9:1 But as touching the eucharistic thanksgiving give ye thanks thus.
Didache 9:2 First, as regards the cup: We give Thee thanks, O our Father, for the holy vine of Thy son David, which Thou madest known unto us through Thy Son Jesus; Thine is the glory for ever and ever.
Didache 9:3 Then as regarding the broken bread: We give Thee thanks, O our Father, for the life and knowledge which Thou didst make known unto us through Thy Son Jesus; Thine is the glory for ever and ever.
Didache 9:4 As this broken bread was scattered upon the mountains and being gathered together became one, so may Thy Church be gathered together from the ends of the earth into Thy kingdom; for Thine is the glory and the power through Jesus Christ for ever and ever.
Didache 9:5 But let no one eat or drink of this eucharistic thanksgiving, but they that have been baptized into the name of the Lord; for concerning this also the Lord hath said: Give not that which is holy to the dogs.
Didache 10:1 And after ye are satisfied thus give ye thanks:
Didache 10:2 We give Thee thanks, Holy Father, for Thy holy name, which Thou hast made to tabernacle in our hearts, and for the knowledge and faith and immortality, which Thou hast made known unto us through Thy Son Jesus; Thine is the glory for ever and ever.
Didache 10:3 Thou, Almighty Master, didst create all things for Thy name's sake, and didst give food and drink unto men for enjoyment, that they might render thanks to Thee; but didst bestow upon us spiritual food and drink and eternal life through Thy Son.
Didache 10:4 Before all things we give Thee thanks that Thou art powerful; Thine is the glory for ever and ever.
Roman Catholics usually pick up on the word "Eucharist" and say "ah ha see just like we have today!" Which, when we look at the Greek word 'eucharistia' it means "Thanksgiving." No more no less. Today to some churces it may mean something more than originally used. How the doctrine of transubstantiation came from what is in the NT and in the Didache is unknown.
By “going into the weeds” I mean let’s not do what we always do and fritter off into a million doctrinal disputes. Of course we fundamentally disagree on the Eucharist, and if this were a thread about that or the Didache I’d be happy to engage on it.
But I am trying to keep this focused on the question at hand.
The claim is that I, as a Christian, should be able to go to my Bible and prayerfully read it and the truth will make itself known to me. Great. Ok. So now what happens if I do that, and I find myself disagreeing with...well...pretty much the whole spirit and doctrinal claims of the Reformation.
My opinion is not infallible. I get that. But it’s still no worse or better than any other believer’s.