A canticle is a religious song which uses text taken directly from the Bible. Numerous examples of such canticles can be heard in performance around the world, in a variety of languages and Christian sects. The setting of Biblical text to music is an ancient tradition, and some very notable composers have written canticles using a wide variety of Biblical excerpts. The only songs from the Bible which are not considered canticles are those from the Book of Psalms.
The idea of putting religious text to music is very old. From a practical stance, canticles allow people to memorize large sections of the Bible in a way which is easy for them, and in an era when books were extremely expensive, this allowed Christians to be mindful of the traditions of their faith. Learning a canticle can also be a good way to teach children about the Bible, as they can be asked to reflect on the words while they learn the music. Religious music is also used to glorify God, with singers offering up their voices as a tribute, and in some cases a canticle may take the form of a tribute or offering of thanks from a composer.
Singing also, of course, just sounds nice, and many churches take advantage of this. Religious worship may as well be enjoyable, especially when one is attempting to win converts, and this undoubtedly explains the proliferation of singing in the early Christian church. Singing also encourages members of the congregation to learn various sections of the Bible and to reflect upon them, thinking about the meaning as the words as they put them to voice.
There are a number of ways to use canticles in religious worship. In a church with a formal choir or group of performers, canticles may be interspersed into the service along with hymns from the Book of Psalms. Some congregations also sing canticles and hymns during the service, accompanied by a choir or musicians, or on their own, led by the officiant.
The mood of a canticle can vary widely, depending on the text selection used and the composer. In many cases, a canticle is joyous, celebrating God and Christian faith, while others have notes of darkness, intended to encourage people to reflect on the nature of faith and the challenges which people may face during their lives. Many fine examples of canticles from throughout Christian history continue to be performed today, both in churches and in concerts which are designed to showcase such music.