There are two features of the Church that are the foundations on which she stands on.
One is the authority that is divinely bestowed on her and we heard about that in the gospel.
The other is the mission of salvation that she is to carry out and proclaim to the world.
It was to St. Peter that Jesus bestowed upon the Church the authority of the truth and St. Paul was called to be the "Apostle to Gentiles" who will carry out the Church's mission to the nations.
Even though Jesus said that the gates of the underworld can never hold out against the Church, that does not mean that there will be no danger or attacks on the Church.
In the 1st reading, St. Peter was imprisoned and faced certain death but the angel of the Lord rescued him out of the prison.
In the 2nd reading, St. Paul testified that the Lord stood by him and gave him power, so that he can continue to proclaim the message of salvation to the pagans.
This feast of St. Peter and St. Paul affirms our faith and that the Lord will rescue us from all evil and danger.
Let us put our trust in the Lord, and may St. Peter and St. Paul pray for us that we will continue to proclaim the message of salvation with truth and with love.