What do people who can't read do? What they've always done--rely on those who can.
In the ancient world you couldn't go pull a scroll off the shelf and read it. Even if you could read. Communities, Christian communities, had copies of Scripture, but these were incredibly valuable--each sheet of papyrus or vellum had to be meticulously hand-written. The way Christian experienced the Bible was by having it read to them.
In the Gospel of Luke where Jesus reads from the Isaiah scroll, that was standard Jewish practice. Synagogues had copies of the Torah and the Prophets (e.g. the Old Testament), and there were set readings for the day. Jesus didn't go and pick up the Isaiah scroll off the shelf and just read what He wanted--the scrolls were the property of the synagogue, and the day in question involved the particular reading from Isaiah, and Jesus was that day's reader. It is noteworthy, then, that the reading for that day was the passage in Isaiah about the future Jubilee, the year of Divine Favor; a passage loaded with messianic subtext--so when the Lord says, "Today this has been fulfilled in your hearing", that's the context of what's going on. Jesus read this on the day this was supposed to be read--Jesus' addition, the out of the ordinary here, is that He says, "Today this has been fulfilled"--a bold declaration that He is the Messiah, the One who brings about YHWH's Jubilee for the world.
The first Christians were all Jews, and they continued to worship in a normal Jewish way. Not only in the synagogues before they were eventually kicked out; but also in their own Lord's Day meetings. That's what Acts chapter 2 talks about--meeting together for prayer, the breaking of bread, and the apostles' doctrine. That's the Liturgy. It's right there at the very beginning, at Pentecost when the Holy Spirit was poured out on all flesh in fulfillment of Joel's prophecy, as Christ Himself said would happen when He promised the Paraclete who would come, and fulfilling the prophecy of St. John the Baptist, "He who comes after me will baptize you with the Holy Spirit and with fire". So that when the Spirit fell, the word went forth, and many were brought to faith in the Messiah, and after receiving Baptism (that Baptism which Christ Himself instituted in Matthew 28:19) they didn't re-invent the wheel for how to do a religious gathering. They retained the liturgical customs they were already familiar with, but these were now distinctively Christian. The homily was a Christian homily, the prayers were Christian prayers, the Scriptures were read and understood now through the revelation of the Messiah. What was especially unique here was the celebration of the Lord's Supper, the bread and wine which was the very flesh and blood of the Messiah broken and shed for them--as He Himself said, and the Apostles faithfully taught.
It was all there, right in the beginning.
Then you should know better.
-CryptoLutheran