The New Testament gives the acts of worship in which Christians are to engage. The acts of worship mentioned in the Old Testament such as dancing, instrumental music, animal sacrifices, special singers, and the burning of incense, were commanded only of the nation of Israel. The Old Testament as a binding law for God’s people ended at the cross (Colossians 2:13,14). Christians must learn from the New Testament, the law of Christ for all people today, how God wants to be worshipped today. The acts of worship required by God are plainly set forth in the New Testament.
The Lord’s Supper
The Lord’s supper or communion (1 Corinthians 10:16) consists of two things: (1) unleavened bread (without yeast) and (2) the fruit of the vine (grape juice). The purpose of the Lord’s Supper is to bring to our remembrance the sacrifice of the body and blood of Jesus on the cross for our sins (Matthew 26:26-29). We must be very careful when we partake of the communion that we discern the blood and body of Jesus so that we partake in a worthy manner (1 Corinthians 11:23-30). Christians are to eat the the Lord’s Supper every first day of every week (Acts 20:7).
Prayer
Prayers offered to God are to be a part of our public worship as well as our private daily devotions. There are many examples and precepts concerning prayer in the New Testament (1 Timothy 2:1,2,8; Philippians 4:6, etc.). In our prayers to God we give thanks and praise His name. In our prayers we can pray for our needs and for the needs of others. Jesus gave us a "model" prayer in Matthew 6:5-15. He did not intend for us simply to repeat this prayer by rote but gave it as an example by which we could pattern our own prayers. Jesus Christ is our mediator and high priest. Therefore, our prayers must be addressed to God in the name of Jesus (John 16:23; 1 Timothy 2:5; Hebrews 4:14-16; 1 John 2:1,2).
Preaching and Teaching God’s Word
God has commanded us to teach His Word (Matthew 28:19,20). Both saved and sinners need to be taught. Therefore, a lesson from the Bible is one of the acts of worship in which Christians are to engage (Acts 2:42). We must learn God’s Word so that we can grow stronger in Christ, teach others, and overcome false teachings (1 Peter 2:1,2; 2 Timothy 2:2; 4:1-5). This is a very important part of our worship and must never be overlooked.
Giving
Giving of our means is a part of our worship to God. This is the way Christ’s church gets the necessary funds to do its work. God has given us the perfect plan for giving (1 Corinthians 16:2). We are told who is to give, "Let every one of you." We are told when we are to give, "Upon the first day of the week." We are also told how much to give, "As God hath prospered us." We show our love for God when we give cheerfully and willingly to Him (2 Corinthians 9:7).
Singing
Christians are commanded to praise God in song (Colossians 3:16). The kind of music God has commanded for His church is vocal music only, that is, singing. There is no command or example anywhere in the New Testament for the use of mechanical instrumental music in Christian worship. To add instruments of music to our singing is a sin for it is adding to what God has told us that He wants. No man has the right to do this (Revelation 22:18,19; 2 John 9-11). We are to "make melody in our hearts" (Ephesians 5:19), the instruments made by God, not instruments made by man!
Neither has God commanded us to have special singers in our worship such as choirs. Every Christian must praise God in song just as every one must partake of the Lord’s Supper for himself. The purpose of our worship to God is not to entertain ourselves. Therefore, what we do in worship is not based on that which appeals to our physical senses, but must be based upon what pleases God!
True Christians want to worship God. In fact, it is impossible for a true Christian not to worship God. When we understand God’s greatness, His glory, majesty, wisdom, and strength, and reflect upon His infinite mercy in giving His only begotten Son to save us from our sins, our hearts will overflow with a "sacrifice of praise to God continually, that is, the fruit of the lips giving thanks to his name" (Hebrews 13:15).