Every year on January 21, the Church gives us such beautiful prayers in honor the Lord and his Virgin-Martyr Agnes. Here is the Collect:

Almighty ever-living God, who choose what is weak in the world to confound the strong, mercifully grant, that we, who celebrate the heavenly birthday of your Martyr Saint Agnes, may follow her constancy in the faith. Per Dominum Nostrum Iesum Christum ...

Here the Church is clearly drawing upon St. Paul's first Letter to the Corinthians (1:29), where St. Paul says that God chooses the weak of this world to confound the strong, that no flesh may glory in God's sight. Then, in Preface I of Holy Martyrs, it is stated:

For the blood of your blessed martyr Agnes, poured out like Christ's to glorify your name, shows forth your marvelous works, by which in our weakness you perfect your power and on the feeble bestow strength to bear you witness, through Christ our Lord.

And so, on this Inauguration evening, as the rich and powerful of this world are having their empty, secular celebrations that last only for a short time, we the baptized faithful rejoice in the eternal love of God shown forth in the Blood of our Lord Jesus Christ and his witnesses, his martyrs, as we give our hearts to Jesus and His Father and their Holy Spirit, one God, as we endeavor to live always in accord with their eternal values.

Almost nothing is known of this saint except that she was very young--12 or 13--when she was martyred in the last half of the third century. ... Agnes is a symbol that holiness does not depend upon length of years, experience, or human effort. It is a gift God offers to all, one he can protect in the most fearful of circumstances. -Leonard Foley, O.F.M., ed. Saint of the Day, Vol. 1, pages 18 - 19.