This is why I suggested that Apostolic Tradition is NOT superior to Scripture - it is not so clear sometimes, although once we identify it, it is equal to Scripture, both coming from God. We (people of today) have to ascertain what the Church has thought about an issue. Rarely is something unanimous. So when the Church explores an issue (say, infant baptism), there is much to consider - unlike Scripture, which is generally more accessible. More study is involved in making this determination of the Spirit's guidance of the Church. Those who disagree with the idea are re-examined more closely. The sacred Liturgy is studied. What has been the common practice? This is a process that takes awhile. This is why I suggested that we can know Apostolic Tradition more CLEARLY through Councils - when the Church defines infant baptism as an infallible teaching.
However, BEFORE the Church actually defined this, the Church taught it "informally" and later "formally", if you will - "everywhere, by everyone in all times". This is called the "sense of the faithful". The Holy Spirit moves the Church as a whole and organic organization through her individuals. But since man does not clearly interpret the Spirit's movements individually, the Church relys on the "general consensus" over time to figure out what the Spirit is teaching the Church as a whole. It is defined at Councils so that EVERYONE can know. Questions about whether something is infallible are no longer made.
Let me see if I can describe the process...
The Apostles taught infant baptism to Christians. In the letters that they address to Corinth or Ephesus, they never mention this. However, it becomes a generally accepted practice, taken for granted, sort of like when Catholics do the sign of the cross. We just do it, perhaps not knowing its origin. A hundred years after the Apostles died, the Church throughout is continuing this practice, even though it is not mentioned specifically in the writings that are becoming accepted as Scriptures. However, some men ARE writing about it. Tertullian, 200 AD, writes that it is an "ancient practice". So does Origen (250 AD). Why do they even write about it? There are some people who question the idea of WAITING 8 days (like circumcision). They want to baptise SOONER!
Thus, Christian writers 100 years after the last apostle died are considering the "ancient" tradition from the Apostles and whether it was acceptable or necessary to even wait 8 days...Cyprian writes in 250 AD that it wasn't necessary (he was a bishop) to wait, and it appears that the Church had followed this idea and taught it to this day. I am not sure at what point the Church officially, in a Council, declared infant baptism as an infallible teaching. I believe it wasn't until some disagreed with the idea that the Church found it necessary to say "yes, infant baptism is allowed". I believe the Council of Trent solemnly declared it. However, the Church's unanimous practice of it BEFORE the declaration is a sign to us that the SPIRIT OF TRUTH was leading the Church to this practice - "everywhere, in every time, by everyone". Thus, the Consensus that Kolo talked about. The Council makes it irrefutably clear, but it was a teaching of the Church before that - recall that the Church has the power to bind and loosen the faith and the content of that faith.
Regards
Thank you very much for your comments on this subject.
If the origin is uncertain, how can you know the Apostles taught infant baptism? You can take certainty from what was only passed down orally, until the writers you cite? Tertullian could have been right, but how can you know for sure? I take it that since I'm not the first to ask, that this is what Councils are for.