He is also the only apostle that did not know Jesus personally and you can read in his letters that this fact caused many people to question his authority. But because of this fact, he became an example for us that belief in Jesus Christ, as the Son of God, is a grace from God. Christ himself spoke of this grace to St Thomas in the upper room. So in many ways, Paul is the only apostle that received Christ as we have; through a grace from God and a willingness to say "yes".
God our Father,
You taught the Gospel to all the world
through the preaching of Paul Your apostle.
May we who celebrate his conversion to the faith
follow him in bearing witness to Your truth.
We ask this through our Lord Jesus Christ, Your Son,
who lives and reigns with You and the Holy Spirit,
one God, for ever and ever. +Amen.