What, from the Bible, was taught in the first century Christian congregation?

Things like:

What Is God’s Purpose for the Earth?

Who Is Jesus Christ?

The Ransom—God’s Greatest Gift

Where Are the Dead?

Real Hope for Your Loved Ones Who Have Died

What Is God’s Kingdom?

Are We Living in “the Last Days”?

Spirit Creatures—How They Affect Us

Why Does God Allow Suffering?

Living in a Way That Pleases God

A Godly View of Life

How to Make Your Family Life Happy

Worship That God Approves

Take Your Stand for True Worship

Draw Close to God in Prayer

Baptism and Your Relationship With God

Remain in God’s Love

The first century Christian congregation included the authors of the New Testament. So you can make a case for saying that all of the New Testament comes from the teachings of the first century Church. The acts and teachings of the Apostles and the Gospels were added to the Old Testament to become the Bible.

And by the same token, none of the New Testament was taught by the first century Christians because the Bible as we know it now wasn't codified until later. What we refer to as Sacred Tradition (those beliefs and practices that have been handed down through the centuries) is the early Church's legacy to us.

I'm not sure which way to interpret your question.

The Hebrew Scriptures, as there was no New Testament in the first century after Yeshua. He and the disciples taught the Torah. And they were able to prove from the Tanak (the Old Testament) that Yeshua was in fact the Messiah.

Well it depends what time in the first century. Early on the bible was not completed and spiritual gifts were given to the faithful to supplement the lack of completed scripture. So prophecy pertinent to the time would be taught and the apostles would speak on matters you would later find in the bible.

Later, when the bible was completed... the whole thing would be taught, not part of it.

the very first christians were jewish. so they were taught both the torah and the teachings of Jesus. it wasn't until Saul/Paul came on the scene that Christianity spread to non jewish or Gentile peoples. and both men and women were taught. historically, only men could go to the synagogue. it was up to the men to educate the women or not, depending on their choice. the new testament was not completed until about 70 AD. so it wasn't until after that point that the new testament was taught as well.

The Blending Or Mixing Of The Law [Judaism] With Grace [Apostle Paul's Epistles, Romans -- Philemon and Hebrews]. . .

The Old Testament law and prophets

The New was not yet available to most

Luk 4:16 ¶ And Jesus came to Nazareth, where he had been brought up: and, as his custom was, he went into the synagogue on the sabbath day, and stood up for to read.

Luk 4:17 And there was delivered unto him the book of the prophet Esaias. And when he had opened the book, he found the place where it was written and began to read.

The coming of Gods kingdom was preached then, and still should be.

That Jesus is the Messiah and that they should preach this message to all nations.

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There was NO BIBLE ib the first century AD -

as the "BIBLE" was not put together untill the FOURTH century AD . . .

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