Here's the great question that came to us: "Is it legitimate for unbelievers to pray the Lord's Prayer?"
The Lord's prayer, or any other prayer for that matter, is heard and answered by God the Father only when we come to Him through faith in His Son, Jesus Christ (John 14:6). Prayer to the true and living God is one of the most precious privileges which Christ purchased for His people through His redemptive work (Hebrews 4:14-16). Those without Christ exist in a state of condemnation; they have thus far refused to repent of their sin and to confess the risen Christ as Lord and Savior (John 3:18). Thus, the most pertinent prayer for them is one which seeks salvation in Christ, not one which presupposes it, as does the Lord's prayer. Praise our merciful God, He hears and gladly answers the cry of all those who seek salvation through Christ! (Romans 10:8-13) Not only does He hear, answer and save the repentant sinner from his or her guilt and sin, He declares that sinner righteous in Christ (Romans 3:21-26). Not only does He declare the sinner righteous in Christ, He actually adopts the repentant sinner as His child (Romans 8:15). And it is as God's children that we take upon our lips the prayer and the kind of prayer the Lord teaches His disciples. Because of Christ's work, they who trust in Him, and they alone, may address God as "Our Father."
If by legitimate you mean acceptable to God, then, no, an unbeliever praying the Lord’s Prayer is not legitimate. Here are three simple reasons why.
First, only prayers of believers are acceptable to God. “The sacrifice of the wicked is an abomination to the Lord, but the prayer of the upright is His delight” (Proverbs 15:8). Only those prayers offered in the name of Christ, i.e. in His righteousness, are pleasing to God. So no prayer of an unbeliever is acceptable.
Secondly, in the immediate context of instruction on the Lord’s Prayer, He warns His disciples not to pray like the Gentiles (Matthew 6:7-8). Gentiles, or unbelievers, think God will listen to them for their piety displayed in their repetition. But clearly Jesus teaches the Father is not impressed with their meaningless repetition and many words. Usually unbelievers use the Lord’s Prayer in the very way (i.e. repetitive) that Jesus was instructing us not to pray. This also serves as a warning to believers not to use it in this manner as well. It is a pattern for godly praying, not a repeated formula for praying.
Finally, note the prayer starts with the address “Our Father.” If one does not know God as Father, then that adds a whole new meaning to the idea of “legitimate.” The unbeliever praying this prayer would be pretending to be a child of God when in fact he is illegitimate. His most immediate need is not to pray the Lord’s Prayer, but to believe upon the One who gave it to us.
The word choice is interesting: if legitimate is defined as "lawful", of course it's legitimate. I know of no Biblical laws preventing anyone from praying the Lord's Prayer. Related would be whether we would allow unbelievers to participate in our worship by singing Psalms to God.
But if we change "legitimate" to "effective", the answer changes radically: no, it is not effective for unbelievers to pray the Lord's Prayer.
First, I want to make clear that (1) God knows and hears everything and (2) has the right to affirmatively answer the prayers of unbelievers. However, in John 9:31, Jesus makes a strong point: _ We know that God does not listen to sinners, but if anyone is a worshiper of God and does his will, God listens to him.__ _This "listening" Jesus refers to is not the listening of knowledge (God hears every prayer!) but the the listening with grace. In other words, God is disposed against unbelievers and disposed toward believers.
So an unbeliever praying the Lord's Prayer isn't doing something inherently unlawful, but until they are joined to Jesus by faith, they also aren't doing something effective. If you know an unbeliever who takes some comfort in repeating the Lord's Prayer while never having God as his Father, encourage them to reject their superstition and seek to be able to pray the Prayer in truth!
Please join the conversation in the comment section!