This is part eight in a series of Tim Keller's thoughts on the Prayer of Prayers.
7 “And when you pray, do not heap up empty phrases as the Gentiles do, for they think that they will be heard for their many words. 8 Do not be like them, for your Father knows what you need before you ask him. 9 Pray then like this:
deliver us from evil.
~ Jesus, Matthew 6:7-9, 13
Calvin combined this phrase with "lead us not into temptation" and called it the sixth and last petition. Augustine and Luther, however, viewed "deliver us from evil" as a separate, seventh petition. It can also be translated "deliver us from the Evil One," that is, the devil. Luther writes that this petition is "directed against specific evils that emanate from the devil's kingdom...poverty, dishonor, death, in short...everything that threatens our bodily welfare."
Augustine indicates that while the sixth petition is for deliverance from the remaining evil inside us, this seventh petition is for protection from evil outside us, from malignant forces in the world, especially our enemies who wish to do us harm.