After the Exodus, God commanded regular and special assemblies to remember what He had done for His people and to honor Him. Wherever they were, whatever they were doing, they were to drop everything and gather as the blessed people. Just giving Him that priority was the beginning of those worship seasons.
Jesus required his followers to remember what God had done for them in a special memorial made up of unleavened bread and wine. Paul called it “the Lord’s Supper.” Early Christians gathered for this purpose on the first day of the week, the day of the completion of Christ’s saving act (his resurrection which declared him to Be God’s son).
The focal point of our Sunday assembly is the Lord’s Supper. It’s observance, accompanied by prayer, is the only required act. Early Christians expanded on this worship of God by reading and teaching God’s word (another manner of worship) and singing hymns of praise to Him. But the Supper is paramount.
The bread represents the body of Christ and by each of us eating it, we remember that Christ, through His sacrifice, has not only made us a part of himself, but has united us all in his body. The unity with Him we have as a group requires us to be united with one another. The fact that the bread is unleavened reminds us that God has, in Christ, made us pure and we are to behave that way every day.
The wine reminds us that our place before God did not come cheap. It cost the blood of Christ. In addition, it reminds us that in drinking it, we have entered into a special relationship with God, a covenant, that in God’s eyes, separates us from the world and makes us special to Him. It is a reminder to be supremely thankful and humble, and to keep a close watch on our behavior because God has made us to be His people.
The worship assembly is not something to be taken lightly, but is to have such priority in our lives that each day is lived in view of the next meeting of God’s gathered people.
 Matthew 26:26-29; Mark 14:22-25; Luke 22:17-20
 It is the “first day of the week” that is given prominence in the New Testament. See Matthew 28:1; Mark 16:2, 9; Luke 24:1; John 20:1, 19; Acts 20:7.
 Romans 1:4
 1 Corinthians 1:17 – 17 Because there is one bread, we who are many are one body, for we all partake of the one bread.
 Paul uses this thought in 1 Corinthians 5:6-8 when he refers to the Corinthian Christians’ behavior – 6 Your boasting is not good. Do you not know that a little leaven leavens the whole lump? 7 Cleanse out the old leaven that you may be a new lump, as you really are unleavened. For Christ, our Passover lamb, has been sacrificed. 8 Let us therefore celebrate the festival, not with the old leaven, the leaven of malice and evil, but with the unleavened bread of sincerity and truth.