Pange Lingua Gloriosi Corporis Mysterium is a hymn written by St Thomas Aquinas

Thomas Aquinas

Thomas Aquinas, O.P. , also Thomas of Aquin or Aquino, was an Italian Dominican priest of the Catholic Church, and an immensely influential philosopher and theologian in the tradition of scholasticism, known as Doctor Angelicus, Doctor Communis, or Doctor Universalis...

 (1225–1274) for the Feast of Corpus Christi

Corpus Christi (feast)

Corpus Christi is a Latin Rite solemnity, now designated the solemnity of The Most Holy Body and Blood of Christ . It is also celebrated in some Anglican, Lutheran and Old Catholic Churches. Like Trinity Sunday and the Solemnity of Christ the King, it does not commemorate a particular event in...

 (now called the Solemnity of the Holy Body and Blood of Christ). It is also sung on Maundy Thursday

Maundy Thursday

Maundy Thursday, also known as Holy Thursday, Covenant Thursday, Great & Holy Thursday, and Thursday of Mysteries, is the Christian feast or holy day falling on the Thursday before Easter that commemorates the Last Supper of Jesus Christ with the Apostles as described in the Canonical gospels...

, during the procession from the church to the place where the Blessed Sacrament is kept until Good Friday. The last two stanzas, called separately Tantum Ergo

Tantum Ergo

Tantum ergo are the opening words of the last two verses of Pange Lingua, a Mediaeval Latin hymn written by St Thomas Aquinas. These last two verses are sung during veneration and Benediction of the Blessed Sacrament in the Roman Catholic Church and other churches that practice this devotion...

, are sung at Benediction of the Blessed Sacrament

Benediction of the Blessed Sacrament

Benediction of the Blessed Sacrament is a devotional ceremony celebrated within the Latin Rite of the Roman Catholic Church, as well as in some Anglican and Lutheran Churches, Liberal Catholic churches, Western Rite Orthodox churches, and Latinised Eastern Catholic Churches.Benediction of the...

. The hymn expresses the doctrine of transubstantiation

Transubstantiation

In Roman Catholic theology, transubstantiation means the change, in the Eucharist, of the substance of wheat bread and grape wine into the substance of the Body and Blood, respectively, of Jesus, while all that is accessible to the senses remains as before.The Eastern Orthodox...

, in which, according to the Roman Catholic faith, the bread and wine are changed into the Body and Blood of Christ

Jesus

Jesus of Nazareth , commonly referred to as Jesus Christ or simply as Jesus or Christ, is the central figure of Christianity...

.

It is often sung in English as the hymn Of the glorious body telling, to the same tune as the Latin.

The opening words recall another famous Latin

Latin

Latin is an Italic language originally spoken in Latium and Ancient Rome. It, along with most European languages, is a descendant of the ancient Proto-Indo-European language. Although it is considered a dead language, a number of scholars and members of the Christian clergy speak it fluently, and...

 sequence

Sequence (poetry)

A sequence is a chant or hymn sung or recited during the liturgical celebration of the Eucharist for many Christian denominations, before the proclamation of the Gospel. By the time of the Council of Trent there were sequences for many feasts in the Church's year.The sequence has always been sung...

, Pange Lingua Gloriosi Proelium Certaminis

Pange Lingua Gloriosi Proelium Certaminis

Pange Lingua Gloriosi Proelium Certaminis is a sixth-century Latin sequence hymn generally credited to the Christian poet St Venantius Fortunatus, Bishop of Poitiers, celebrating the Passion of Christ. In the Catholic Church, the first five stanzas are used at Matins during Passiontide in the...

, by Venantius Fortunatus

Venantius Fortunatus

Venantius Honorius Clementianus Fortunatus was a Latin poet and hymnodist in the Merovingian Court, and a Bishop of the early Catholic Church. He was never canonised but was venerated as Saint Venantius Fortunatus during the Middle Ages.-Life:Venantius Fortunatus was born between 530 and 540 A.D....

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There are many English translations, of varying rhyme scheme

Rhyme scheme

A rhyme scheme is the pattern of rhyme between lines of a poem or song. It is usually referred to by using letters to indicate which lines rhyme. In other words, it is the pattern of end rhymes or lines...

 and meter

Meter (poetry)

In poetry, metre is the basic rhythmic structure of a verse or lines in verse. Many traditional verse forms prescribe a specific verse metre, or a certain set of metres alternating in a particular order. The study of metres and forms of versification is known as prosody...

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