* What is Church? ( Read in detail on the Body of Christ )
In the Greek it is "ekklesia= 'called out people'. So the church is made up of those who are saved by faith in the Lord Jesus Christ and are separated from the world unto Him. It is NOT a building but God's People.
The Church is also known as the Body of Christ. There are two aspects of the Church: One is the Universal Church, made up of all past, present and future saints.
And the other is the Local Church, the present gathering of saints at a particular geographical location.
In the Book of Acts we read the history of the early church in the transitional stage. In the Epsitles, we have the clear explanation and teaching about the Church.
Acts 2:41-47; Rom. 16:5; 1Cor.1:2; 16:19; Eph. 1:22,23; 5:23-32.

* The Functions & Ordinances in the Church:
There are mainly four functions we read about in Acts 2:42.
1. Apsotles teaching: studying the word of God systematically (2Tim.2:15).
2. Fellowship: gathering regularly and sharing together.
3. Breaking of bread: Holy Communion: Maintaining unity at the Lord's table.
4. Prayers: Corporately for one another and the work of the Lord.
In addition, there: was praise, worship, sharing in one another's needs (social concern), witnessing, etc.
The Two Ordinances the Lord has given to the Church are:
1. Water Baptism: to baptize the believers, accepting them into His Church.
2. Communion: to remember the Lord's death and resurrection till He comes back.
The Primary task of the Church is contained in the Great Commission the Lord has given to His disciples in Matthew 28:18-20. To go Make disciples of all nations.i.e. to preach the gospel of salvation to save souls and build His Kingdom.

Every saved, born again believer must associate himself with a Bible-believing, Christ-centred Church. The Church is in the centre of God's plan and work in the world today. You must be actively involved in a local church to be of use to God.

Read complete details in a separate article on the Body of Christ.