"The Lord did not content himself to teach us to pray only with his words, but he also gave us his example. We often see him in prayer; he gives us the example we must follow. It is written: “he went off to a lonely place, in the desert to pray”. And elsewhere: “he departed to the mountain to pray, and he spent the night in prayer to God”. If already the one who was without sin prayed in this way, all the more reason for us sinners to pray like this. If he spent the night in prayer, all the more reason for us to pray constantly and to be, us as well, always on watch.
The Lord prayed and interceded not for himself – for which sin would he, the innocent, need to ask to be forgiven? – but he prayed for our sins. This is proved to be true when he tells Peter: “Remember that Satan has demanded to sift all of you like wheat, but I have prayed that your own faith may not fail”. Later on he prayed the Father for all of us, when he says: “I pray not only for them, but also for those who will believe in me through their word, so that they may all be one, as you, Father, are in me and I in you”.
Oh, how great are the mercy and goodness of God, in favor of our salvation! He did not content himself to redeem us through his blood, but he also beforehand wished to pray for us. But take notice of the desire of the one who prays: as the Father and the Son are one, that we too may live in unity."
-St. Cyprian of Carthage