In Christianity, worship has been considered by most Christians to be the central act of Christian identity throughout history. Many Christian theologians have defined humanity as homo adorans, that is, the "worshipping man," and thus the worship of God is at the very core of what it means to be human.
Throughout most centuries of Church history, Christian worship has been primarily liturgical, characterized by formal, set prayers and hymns done in a particular order according to specific rituals, whose texts were rooted in, or closely related to, the Scripture, and particularly the Psalter. Set times for prayer during the day were established (based on Jewish models), and a festal cycle throughout the Church year governed the celebration of feasts and holy days pertaining to the events in the life of Jesus and also of the saints of both the Old Israel and the New (the Church).
A great deal of emphasis was placed on the forms of worship, as they were seen in terms of the Latin phrase lex orandi, lex credendi ("the rule of prayer is the rule of belief")—that is, the specifics of one's worship express, teach, and govern the doctrinal beliefs of the community. To alter the patterns and content of worship were to change the faith itself. As such, even though there was always a certain amount of variety in the early Church's liturgical worship, there was also a great deal of unity. Each time a heresy arose in the Church, it was typically accompanied by a shift in worship for the heretical group. Thus, orthodoxy in faith also meant orthodoxy in worship, and vice versa. Even the very word orthodoxy means both "right faith" (literally, "straight opinion") and "right worship" (literally, "straight glory"). Thus, unity in Christian worship was understood to be a fulfilment of Jesus' words that the time was at hand when true worshippers would worship "in spirit and in truth" (John 4:23).
Worship: At the Heart of Our Relationship with GodThe Westminster Shorter Catechism begins as follows:
1. What is the chief end [i.e. goal] of man?
A. Man's chief end is to glorify God, and to enjoy him forever.
This reflects a common Christian perspective that all of Christian life is focused on God and on our fellowship with him and other people. Our care for others is in this context. That doesn't mean that others are only side-issues: loving others means that we genuinely care about them. However Christian experience is that our relationships with other people must be put into the context of a relationship with God, or those relationships will start to become unbalanced.
For many Christians, worship is at the heart of our relationship with God, both as individuals and a community. In worship we focus on God: on hearing a message based on the Bible, on prayer, and on the sacraments. Of course individual Christians can do many of these things in private. However in worship we ground our life as a community in a corporate experience of God.