While the Ordinary consists of six sections, Renaissance composers only set the first five to music in their compositions.
1) The Ordinary begins with the Kyrie. The text translates to "Lord have Mercy, / Christ have Mercy, / Lord have Mercy." In this section, congregants, mindful of their sin, beg for mercy from two aspects of the trinity, the Father and the Son.
2) The Ordinary then continues with the Gloria, an adoration of God's glory. One translation of the text is as follows:
Glory in the heights to God
And on Earth peace to men of good will.
We praise You. We bless You.
We adore You. We glorify You.
We give You thanks for Your great Glory.
Lord God, heavenly king, God the Father almighty.
Lord the only-begotten Son, Jesus Christ.
Lord God, Lamb of God, Son of the Father.
3) This is followed by the Credo: "We believe in one God, the Father, the Almighty Maker of heaven and earth, of all that is seen and unseen," a succinct summary of theological belief.
4) Forth is the Sanctus: "Holy, holy, holy / Lord, God of hosts! / Heaven and Earth are full of your glory. / Hosanna in the highest!"
5) Finally is the Agnus Dei: "O Lamb of God, that takest away the sins of the world, / Grant them rest. / O Lamb of God, that takest away the sins of the world, / Grant them eternal rest."
Thus the sections have something of a symmetry to them. A cry for mercy, adoration, a declaration of faith, adoration, and a cry for mercy.