The Our Father is a surprisingly complex prayer that has many layers of meaning. Each petition can refer to multiple spiritual realities if we take the time to reflect upon it.
One example is the petition "lead us not into temptation," which refers not only to temptation in the present moment, but also to the future.
The final battle
The Catechism of the Catholic Church comments on this eschatological meaning in its section on prayer, exhorting us to be vigilant:
Such a battle and such a victory become possible only through prayer. It is by his prayer that Jesus vanquishes the tempter, both at the outset of his public mission and in the ultimate struggle of his agony. In this petition to our heavenly Father, Christ unites us to his battle and his agony. He urges us to vigilance of the heart in communion with his own. Vigilance is "custody of the heart," and Jesus prayed for us to the Father: "Keep them in your name." The Holy Spirit constantly seeks to awaken us to keep watch.
Vigilance against temptation is an ever present need, as we are constantly being enticed away from God by the evil one.
Furthermore, the Lord's Prayer also urges us to be vigilant against the final temptation, at the end of our lives as well as at the end of the world:
Finally, this petition takes on all its dramatic meaning in relation to the last temptation of our earthly battle; it asks for final perseverance. "Lo, I am coming like a thief! Blessed is he who is awake."
The Catechism is quoting from the book of Revelation, which can be interpreted as a preview of what could happen at the end of all things.
And I saw, issuing from the mouth of the dragon and from the mouth of the beast and from the mouth of the false prophet, three foul spirits like frogs; for they are demonic spirits, performing signs, who go abroad to the kings of the whole world, to assemble them for battle on the great day of God the Almighty. (“Lo, I am coming like a thief! Blessed is he who is awake, keeping his garments that he may not go naked and be seen exposed!”) And they assembled them at the place which is called in Hebrew Armaged′don.
We do not know the day or the hour when we will face a final temptation, and so we pray in the Lord's Prayer for strength to endure it.
