1) Scripture is sufficient for all things (“Now one might write at great length concerning these things, if one desired to go rate details respecting them; for the impiety and perverseness of heresies will appear to be manifold and various, and the craft of the deceivers to be very terrible. But since holy Scripture is of all things most sufficient for us, therefore recommending to those who desire to know more of these matters, to read the Divine word, I now hasten to set before you that which most claims attention, and for the sake of which principally I have written these things." (Athanasius, To the Bishops of Egypt, Ch 1, 4)
When the Church Fathers, including St. Athanasius, affirms the sufficiency of Scripture, they do not exclude, but SUPPOSE Tradition! For example, after St. Athanasius says "The Sacred Scriptures are sufficient to indicate the Faith in Christ", he adds "There are many books of our teachers which, if any one will read, he will in some manner understand the interpretation of the Scriptures and might know what he desires" (Athanasius, Orat. C. Gent., N. 1)
When Vincent of Lerin states "the canon of Scripture is perfect and is abundandtly sufficient to itself and to anything else", he adds that the Faith must be safeguarded, "first by Law of Divine Authority (Scriptures) and then by the Tradition of the Catholic Church". (Commonit., CC. I-II). He declares the reason for this double security in his famous sentence "because not all men accept the same sense of Sacred Scriptures, on account of their loftiness...hence, it is most necessary, on account of so many errors, that the line of prophetic and apostolic interpretation be drawn according to the rule of the ecclesiastical and Catholic sense" (Commonit. C. II).
The statements of the Fathers are therefore different then what you are trying to prove - that the Scriptures contain all that is necessary for salvation. The Fathers have always minded the Apostolic Succession, whose teaching and understanding is to be the course and rule in INTERPRETATION of Scriptures. They DO NOT separate the Scriptures from Tradition. Therefore, not all truths are clear from Scripture alone. What is clear is not clear enough to all the faithful. Proof of this is the Real Presence of the Eucharist - "clearly" stated in Scripture, but not believed by many Protestants of who read the Scriptures.
Nothing the Fathers say about Scripture excludes the Tradition of the Church, as it chronolicially and theologically PRECEDED Scripture.
Regards
The Pharisees followed tradition. They were wrong.
The Bereans searched the scriptures. They were right.
Do we see a pattern here?