Our Father, who art in heaven,
     hallowed by thy name,
     thy kingdom come,
     thy will be done,
     on earth as it is in heaven.
Give us this day our daily bread,
And forgive us our trespasses,
     as we forgive those who trespass against us,
and lead us not into temptation,
     but deliver us from evil.
For thine is the kingdom,
     and the power, and the glory,
     forever and ever.
Amen.

Because Jesus is the author of the prayer in this passage, it’s undoubtedly the greatest and best prayer. For if this good, faithful Teacher had known a better one, he certainly would have taught it to us. This doesn't mean a prayer that doesn't use these exact words is worthless. For prior to Christ’s birth, many believers who had never heard these words also prayed. But we should be cautious about other prayers that don’t convey the meaning of this prayer. The psalms are good prayers, and they express the same thoughts as the Lord’s Prayer but don’t express them as clearly. So it’s a mistake to prefer other prayers over this one. Watch out especially for those written out with titles decorated in red ink, in the hope that God will give us health and long life, possessions and honor, indulgences to free us from punishment, and so on. Through these kinds of prayers, we pursue our wills and our honor more than God’s will and his honor. Many people have begun regarding these other prayers more highly than the Lord’s Prayer. Not that I completely disregard these prayers, but people put too much confidence in them. Subsequently, the true Lord’s Prayer, which is inner and spiritual, is despised.

All forgiveness, all blessings, all that is useful, and everything else that people need for their bodies and souls on earth and in heaven overflow from this prayer. It would be better if you prayed one Lord’s Prayer—praying it with all your heart, really thinking about the words, and letting it change your life for the better—than for you to recite all other prayers combined.

-- Martin Luther, in Faith Alone: A Daily Devotional