The religious life of the Christian aims to bring the believer closer to God in various ways. This happens through worship and adoration of God and prayer, which either brings believers into contemplation of Jesus and his life (and of saints who lived a Christ-like life) or places them into a conversation with God. While much of worship takes place according to the cycles and festivals laid out in the Time and Worship Page, it is prayer that forms the centerpiece of religious life in Christianity.
All Christians are enjoined to pray regularly, in both fixed and free forms. Public prayer in particular became fixed. The early church took from Judaism the idea that prayer should occur at particular times of the day. And while the prayers themselves were rather fluid, there was great emphasis on when they were said. After Constantine, the wording of the prayers themselves became fixed. During the Reformation, the Protestants rebelled against much of the fixed nature of prayer and emphasized its spontaneous and free-form character, even in public, group prayer.
There are several different types of prayer. (1) It is used to praise God and to give thanks for his gifts. Such thanksgiving can be for his gifts to all humanity (such as salvation) and for blessings he has given to individuals. (2) Prayer can also be used to petition God, to ask him for particular blessings and favors. (3) Penance also forms an aspect of prayer. Believers may ask for forgiveness for their sins, and may pray in different ways, repenting of their actions. (4) Prayers for both petitions and forgiveness may seek intercession as well. That is, the Christian may ask a saint to pray with them, on their behalf, to obtains the desired request. (5) And, finally, contemplation forms an important part of prayer, whether the Christian contemplates the three figures of the godhead, the events of the salvation history of Jesus' life, or saints and other holy figures who have led a Christ-like life.
The Ave Maria Prayer in Roman Catholicism provides a good example of a prayer that both praises God and asks for intercession.
Hail Mary, full of Grace!
The Lord is with thee.
Blessed art thou among women,
and blessed is the fruit of thy womb, Jesus.
Hail Mary, Mother of God,
Pray for us
Now and at the hour of our death.
The first four lines of this prayer are clearly praise, with the speaker blessing Mary for her role in bringing Jesus to earth. The last three lines are a request for intercession, to help the believer overcome their sins--particularly at the time of their judgement at death.
The one fixed prayer that all forms of Christianity have said is the Lord's Prayer (a.k.a. the paternoster, or "Our Father"). This prayer, which the Gospels record as being taught by Jesus to the disciples, is the oldest prayer formulation in Christianity. Its links to Jesus have given it a divinely inspired character which has preserved it even through the many religious and theological differences of Christian history. It is primarily a prayer of petition, with the Christian asking for both daily sustanence and forgiveness of their sins.
The Rosary is the prayer of contemplation par excellence. Divided into three parts, each part brings the speaker to contemplate five different mysteries of Christ and the enactment of his salvation drama on earth. The first five are the Joyous mysteries, which recall events surrounding his birth. The second five are the Sorrowful mysteries, which recall aspects of his death. And the third five are the Glorious mysteries, which recall his resurrection and ascension, the descent of the Holy Spirit, and the ascension and crowning of Mary. The contemplation of each mystery is accomplished with the praying of the Lord's Prayer, ten Ave Maria prayers, and a Doxology (i.e., "Glory be to the Father...). To help the speaker keep track of the prayers in the midst of contemplation, a string of beads (called Rosary Beads) are used to help count. (For further explanation of the Rosary, go here. For a computer version of the Rosary prayer, complete with the computer equivalent of Rosary Beads, go here.)
While the laity and priests within the church are expected to pray when they can, monasticism raised prayer to its highest form. The whole point of monasticism is to live a life of prayer. Monks and nuns organize their days so that they pray at regular intervals throughout the day, beginning in the early morning and ending late in the night. When this became a fixed practice, it was called the Liturgy of the Hours. (For futher information and the text of the Liturgy, go here.)
As mentioned above, the Reformation rebelled against much of the fixed character of prayer. This included getting rid of composed prayers, as well as rejecting monastic orders devoted to prayer. Instead, all Christians were expected to prayer regularly and frequently, pouring forth praise and petition "from the heart" rather than recite memorized words "from the head."
The head was intended for reading the Bible. Against Church Tradition, the Protestants emphasized Scripture. To varying degrees, the different denominations expected each and every believer to read, memorize and understand the Bible, its stories, and its witness of God.