Ancient sources: Church Fathers about the Unwritten traditions

Where to read about: Church Fathers discussing the unwritten traditions of the church before year 400 AD. I read that Epiphanius of Salamis has said something about the unwritten traditions in his book - Ancoratus I found this https://dokumen.pub/ancoratus-0813225914-9780813225913.html But I can not find something relevant in this book by searching by keywords. Do you know other church fathers discussing the unwritten traditions and the explanations about these unwritten traditions before 400 AD? Thanks in advance. ---------------------- **Looking to find answers on these traditions and more, from ancient writers:** Both catholic and orthodox may be in strange position for some of these traditiosns. What can be the explanations. 1. The catholics with the **Clerical celibacy**. Is this apostolic unwritten traditions that the apostles taught 2 Thes. 2:15; Peter was married Matt. 8:14-15; 1 Corinthians 9:5-7; Also 1 Titus 1:6-9; Timothy 3:2-5; 2 A bishop then must be blameless, the husband of one wife.... About forbidding marriages 1 Timothy 4:1-3; The catholic teaching of the Clerical celibacy seems not to align with scripture or I may not understand it properly, please correct me if I am wrong, not sure how to understand this. If the scripture say Timothy 3:2-5; If this is not apostolic teaching, how can I be 100% sure that the other claimed unwritten traditions are apostolic teachings? Since while researching I learn that there are indeed traditions in the churches that are not apostolic, even borrowed from older pagan traditions like the halo on the icons. 3. Leavened or Unleavened Bread - which one is apostolic and who evt. changed the apostolic tradition and when? As far as I know catholic and orthodox condemn each other on this. 4. If Purgatory is apostolic traditions why do Eastern Orthodox do not accept it? Did ancient writers from East or West mentioned it? Both churches claim to accept "the unwritten traditions" of the apostles. 5. Orthodox do not accept - (Original Sin) but accept Augustine since he is mentioned in ecumenical councils. This is also strange, accepting the person as church father, but not accepting his teachings. 6. Saturday fasting - Orthodox do not do it, if I am not wrong they condemn it. Is this apostolic tradition? 7. Filioque - the original Creed did not include it, it is known to be later addition, so this can not be directly said to be apostolic, also I do not find it in the scripture, even that I have heard, some protestants claim that. The other strange thing is that, Augustine seems to have the filioque and again the orthodox accept him because he was accepted in some of the ecumenical councils, but reject some of his teachings.