As New Testament Christians, we worship God the way He wants to be worshipped, in spirit and in truth (John 4:24). We worship Him with the right attitude and in accordance with His word (John 17:17). We do not have the authority to add to or take away from His word nor do we want to (Rev 22:19). The early church met on the first day of the week (Sunday) to worship God (Acts 2: 42, 20:7). We follow suit.
In any relationship, communication is key to making it successful. In our relationship with God, we must communicate with Him on a daily basis (1 Thess 5:17). We speak to God through prayer and He speaks to us through His word (2 Tim 3:16-17). When the early Christians came together to worship God, they prayed. We pray to God the Father in the name of Jesus Christ, our only mediator between God and man (1 Tim 2:5).
PROCLAIMING GOD'S WORD
When the church gathers together, the word of God is preached (Acts 20:7). Preaching serves to instruct and edify the church (2 Tim 4:2). It is designed to nurture and encourage God's people as well as to convert the lost (Rom 1:16). The teaching of God's word is an essential part of worship. It is the source of food that Christians need to maintain their spiritual strength.
Why do we give our money to a weekly collection? Why did the early Christians come together on the first day of the week to give to a common treasury (1 Cor 16:1-2)? Is it because God needs our money? Is it to make the preacher a rich man? The answer is an obvious no. God designed giving so that we may demonstrate our love for one another (James 2:24). We give as we have been prospered (1 Cor 16:2) and with a cheerful heart (2 Cor 9:6-7). The free-will offerings are used to support the work of His kingdom and the spreading of the gospel throughout the world. As Jesus taught, if we cannot be faithful in small matters, such as handling money for the use of His kingdom on earth, how can we be faithful in greater matters (Luke 16:10)?
The Lord's Supper was instituted by Jesus the night before His crucifixion (Matt 26:26-28). The bread which represents the body of Christ that was given up for us, and the fruit of the vine which represents the blood of Christ that was shed for the remission of our sins, was observed upon every first day of the week by the early disciples to remember His sacrifice (Acts 2:42). Not only does the memorial serves as a reminder of what Christ has done for Christians but it is a testimony to non Christians about the love of Christ for sinners.
We are the crown jewel of God's creation (Psa 8). We understand that our vocal cords, which were created by God, are far more superior to any musical instruments that man can create. Therefore, you will not see any man made instruments in our worship because God has instructed us to sing and make melody with our hearts (Eph 5:19, Col 3:16). We are the musical instruments that God wants in His worship.