So often we hear repeated the prayer found in Matthew 6:9-13.  Unfortunately it has been called the Lord's prayer while actually it is a sample prayer, or a model prayer, for those present to hear the sermon on the mount of Matthew 5-7.  Unfortunately the repetition of that prayer has diminished its significance as a model for how men ought to pray and has actually made its use more like the attitude which Christ was condemning just two verses prior, "But when ye pray, use not vain repetitions, as the heathens do:  for they think that they shall be heard for their much speaking."  In other words when this prayer is just repeated it is empty.  Why not do what Jesus intended and use this prayer as a model for others.
    Also, one aspect of the prayer has changed.  Notice when Christ taught them how to pray, it was before the establishment of the kingdom in Acts 2, and He included this line, "Thy kingdom come."  The kingdom, or church, was yet to be established.  Were we to pray this prayer today, we would need to say "Thy kingdom has come."  Matthew 16:28 showed that the kingdom would be established while some of those remained alive, why then do some today hope that the kingdom will come when prophecy has already been fulfilled?
    A last note concerning this prayer is that we are to pray by Jesus' authority (Matthew 28:18) or through his name, and that is not illustrated in the prayer since Christ Himself was speaking it.  We pray to God with Christ as our mediator (I Timothy 2:5), or advocate (I John 5:1,2), and so we would indicate this in our prayer.
    We may effectively pray the model prayer only when we are not vainly repeating it, are speaking of the kingdom as having been established, and when we direct the prayer to God in the name of Christ.