At the time of Christ, Jews lived in Synagogue communities that supported their members in good times and in bad. If a member committed a serious sin, they could be expelled from their community. These Jews celebrated a Passover like meal on Friday in their homes. During the Last Supper, Jesus evolved this Seder meal into our Liturgy of the Eucharist. During the Synagogue service on Saturday, the Jews would begin with a Call to Prayer called the Shema- Hear, O Israel, the Lord your God is One. This would be followed by prayers and petitions to God. Then there would be readings from the Torah. Then there would be readings from the Prophets and histories. A sermon would follow encouraging imitation of what is taught by the readings. Then there would be Psalms to praise God, followed by prayers asking for God’s blessing. The Synagogue service would end with Aaronic blessing: May the Lord bless you and keep you; May His face shine upon you and be gracious to you; May the Lord lift up his countenance upon you and give you peace. This developed into our Liturgy of the Word.
The Early Christians combined the two worship services of the Jews to become our Mass on Sunday. Sunday worship is established in the Didache about 70 AD. Early Christian worship is described by Justin Martyr in 155 AD in his first Apology starting at chapter 65. In 215 AD, Hippolytus of Rome wrote down many of the Early Church practices, including what they did when they gathered for Mass on Sundays.
Jews still hold a Passover-like meal on Friday and worship on Saturday. Catholics continue to offer the combined Friday and Saturday traditions on Sunday. The Jews had an ordered way to worship and many Christian churches follow the ordered worship procedure of the Early Christians. Today, the Jews keep the Word of God in the Tabernacle. Catholics keep the Word made Flesh in the Tabernacle. Jews stand during the reading of the Torah (first 5 books of Moses). Catholics stand during the Gospel readings. The Jews brought their boys into covenant with God after 8 days. Catholics bring our babies into covenant with God through Baptism. Synagogues had two offices: the Ruler of the Synagogue and the Servant of the Synagogue. These offices became the Offices of Bishop and Deacon in the Early Church. Synagogue communities cared for their members and Christian communities continue to care for their members. The Jews use incense to represent our prayers rising to God and we Catholics continue to use incense for the same reason. The Jews confessed their sins to a Priest who told them what to offer for their sins. Catholic Priests continue to tell repentant sinners what to do for penance. The Jews wore decorated robes when performing their duties on God’s behalf. Catholic Clergy continue to wear decorated robes when celebrating the Mass. The Jews that lived outside of Jerusalem prayed three times a day facing Jerusalem. The Didache required the Early Christians to pray the Lord’s Prayer three times a day. The Jews fasted on Tuesday and Thursday. The Didache required the Early Christians to fast on Wednesday and Friday. We are still required to fast, or offer something else in penance, on Fridays. The Jews had the Sanhedrin to decide matters of law. The Catholic Church started holding Synods and Ecumenical Councils to determine matters of Church practice from the beginning. This is first recorded in the Book of Acts at the Council of Jerusalem, where the Apostles discussed and decided how much of the Jewish Law was still binding on Christians.
From all of this, we understand Catholic Christianity is an evolution of Second Temple Judaism. We are the Church that existed from the beginning and picked the books that would later become the Bible.