Apart from the fact that God encourages Christians not to give up meeting together as some are in the habit of doing,¹ there are many other reasons why we should attend church.

First of all, the church helps us grow as Christians.  Not only do we learn more and more about God, but as we're involved in the ministries of the church (such as Bible study), we come to learn more of what the Bible has to say about living a victorious Christian life; a life that is most pleasing to God.

A Bible study class is also a great place to meet and be actively involved with other Christians.  For some, it's a place where they can serve the Lord and others; as a teacher or other worker. 

God encourages His children to use the Spiritual gift that all His children receive from Him, through the Holy Spirit, serving others; faithfully administering His grace in its various forms.²

The church worship service is also a great time when we, as a body of baptized believers, get to come together as a group in praise and worship of God.  To miss the Sunday morning or Sunday evening worship service is like starting the week off on the wrong foot; it's like having a void in one's life throughout the week.

Being actively involved in a local Christian church, also, helps to keep us accountable for the things we do in life.  When we separate ourselves from the church, we begin to drift in our Christian life.  We become more and more involved in the ways of the world and less in the ways of God.

Yes, it's true that church attendance doesn't make one a Christian; faith in Christ Jesus as Lord and Savior does.  One who is a Christian, however, will not live as good a Christian life as they would have had they been involved in a local Christian church; a church that believes in and teaches the Bible; a church that lifts up and preaches Christ Jesus.

Bible References:

¹ (Hebrews 10:25)

² Peter 4:10)