““Pray, then, in this way: ‘Our ημων Father who is in heaven, Hallowed be Your name.” Matthew 6:9
Contextually it appears that Jesus is instructing the individual to pray
“But you, when you pray, go into your inner room, close your door and pray to your Father who is in secret, and your Father who sees what is done in secret will reward you.” Matthew 6:6
So why address God as our Father and not as my Father?
Prefacing the prayer of the Our Father, Jesus says, “Pray, then, in this way.” In this way could mean not only in the same words but also in the same spirit.
from Ellicott's Commentary
(9) After this manner.--Literally, thus. The word sanctions at once the use of the words themselves, and of other prayers--prescribed, or unpremeditated--after the same pattern and in the same spirit.
The OP’s question brings to mind the parable of the Pharisee and the Tax Collector. In contrast to the prayer of the Our Father, the words of the Pharisee in the parable set an example of how one should not pray. Examining his words, the frequent use of the first person singular puts the focus of the prayer on the Pharisee himself.
The Pharisee having stood by himself, thus prayed: God, I thank Thee that I am not as the rest of men, rapacious, unrighteous, adulterers, or even as this tax-gatherer; 12 I fast twice in the week, I give tithes of all things -- as many as I possess. – Lk 18:11-12 YLT
In contrast, there is a notable lack of the first person singular in the prayer of the Our Father. The natural effect is to orient the person toward God and away from the self.
“Pray, then, in this way: ‘Our Father, who is in heaven, Hallowed be Your name.10 Your kingdom come. Your will be done, On earth as it is in heaven.11 Give us this day our daily bread.12 And forgive us our debts, as we also have forgiven our debtors.13 And do not lead us into temptation, but deliver us from evil.’ – Mt 6:9-13 NASB
In the parable the Pharisee “stood by himself,” and the words of his prayer reflect this individualistic stance. In praying “our Father,” the person is placed in the position where they cannot stand alone. The syntax itself thus acts as a reminder that we can only come before God when we stand with Christ and in sympathy and fellowship with one another.
This is a great question. In Matt 6.6, prayer is described as a private act done in secrecy by the individual:
Matt 6.6 [LEB]:
But whenever you [singular] pray, enter into your[singular] inner room and shut your[singular] door and pray to your[singular] Father who is in secret, and your Father who sees in secret will reward you.
It's all singular. But when describing the disciple's prayer, he addresses the crowd in plural and continues with the plural usage, suggesting a collective prayer:
Matthew 6.9-13 [LEB]:
Therefore you [plural] pray in this way: "Our father [..] give us [..] forgive us [..] do not bring us [..] deliver us [..]"
And the same use of plural appears in Luke 11.2-4.
So is it a private prayer done in an individual closet or a public collective prayer? I think it is a collective prayer that is supposed to be repeated in private, but because the prayer applies to the group, the plural form is used.
The prayer Jesus taught his disciples fits exceedingly well within a wider Jewish setting. And, Jewish prayer overwhelmingly favors framing prayers in terms of "we" instead of "I."
For instance, the Amidah has been prayed at every synagogue service since before the first century. It begins, "Blessed are you, O Lord our God and God of our Fathers..." Another well-known prayer is named "Avenu Malkenu," which means "Our Father, Our King."
More than one scholar has pointed out that Jesus' habit of praying singly to his Father sounds surprisingly bold within Jewish expectations. It even appears to be a messianic claim. Why? Because when God promised King David that from his house would come a descendant who would have a kingdom without end, it says, "I will be to him a father, and he shall be to me a son." (2 Sam 7:14) Only the Messiah would have such intimacy with God that he would speak to him as a single person.
When your days are fulfilled and you lie down with your fathers, I will raise up your offspring after you, who shall come from your body, and I will establish his kingdom. He shall build a house for my name, and I will establish the throne of his kingdom forever. I will be to him a father, and he shall be to me a son. (2 Sam 7:12-14)
One more thing to note is that when Jesus teaches, he almost always addresses his audience in the second person plural (umeis, "y'all"), he isn't speaking to "you" as an individual. When he said, "You are the light of the world," he meant "You all together are the light of the world," not, "Each one of you is a light to the world." English speakers read themselves individually into every "you" and misunderstand what the text is actually saying. Jesus was teaching his disciples as a group how to pray, not telling each one of them to pray all by themselves.
It is true that Jesus often referred to the Father as, "My Father", Matt 11:27, 12:50, 18:35, 20:23, 26:53, Luke 10:22, 15:58, John 5:17, 8:19, 54, 10:17, 18, 29, 14:21, 23, 15:18, etc.
The start of the Lord's prayer with "Our Father", was intended to teach the disciples how to pray and address God. This was obviously adopted by the NT writers who used it regularly, Gal 1:4, 1 Thess 3:11, 2 Thess 2:16, Titus 1:4, Col 1:3, Phil 1:2, 4:20, etc.
This idea of God as "The Father" of Israel was an idiom taken from the OT:
This is consistent with the OT declaration that Israel was the adopted "Son(s) of God" -
Paul uses the same language in the NT, Rom 8:15, 23, 9:4, Gal 4:5, Eph 1:5. This is consistent with the NT doctrine of Adoption and Christ being our brother, Heb 2:11-13, Matt 12:48, 49, John 20:17, Rom 8:29; see also Ps 22:22, Isa 8:17, 18.
Therefore, when Jesus taught His disciples to address God as "Our Father", he was alluding to the OT idiom, His personal identification with the sinners He came to save and God's willingness to adopt us as His children by redeeming us.
Jesus was not establishing specific wording of a prayer to be repeated over and over, as he states in vs 7. Referring to God as our Father is inclusive of all true believers and how they should feel toward their Heavenly Father. It can remind us of our equal standing as children of God. It draws all Christians into a unity like a family. We are all from the same Father...... "our" Father. God
