Understanding the Lord’s Prayer (5): Thy will be done on earth as it is in heaven

Based on what we have understood from what precedes this this petition is quite clear. He wants us to become like our Father, to be with him in His kingdom. To do so we ask that we be able to do what He wills for us, to be like the angels in heaven.

Saint Cassian writes,

Human beings should be like angels and that, just as God’s will is fulfilled by them in heaven, so also all those who are on earth should do not their own will but His will.P 342

Saint Cyril says,

We supplicate, that power may be given to the dwellers upon earth to do the will of God, and imitate the conduct practiced above in heaven by the holy angels. 

Saint Theophylact reminds us that we are asking to be as obedient as the angels. He says,

Just as the angels do Thy will, the Lord says, also grant us to do the same.

Theophylact on Matthew p 58

What is necessary for us to be able to do this? What kind of help are we asking for? First, we need His help to know ourselves more deeply, to help us see what we do that is not according to His will. Then we want to have the strength to condemn this aspect of our life and to make changes, to overcome old habits and establish new ones that conform to His will.

Gregory of Nyssa says,

To say to God, "Thy Will be done also in me," it is entirely necessary first to condemn that manner of conduct which is lived outside the divine will and to fully own up to it in confession.

Saint John Chrysostom tells us that we are to make our life here on earth as in heaven, he says,

He hath bidden us make the earth a heaven and do and say all things, even while we are continuing in it, as having our conversation there; insomuch that these too should be objects of our prayer to the Lord. 

Saint Cyril writes

Those, therefore, who in their prayers ask that the will of God may be done also on earth, should "cleanse [them] selves from every defilement," leap out of the pitfalls of iniquity, and make "perfecting holiness in the fear of God" (2 Cor. 7: 1), that as Paul also says, even while walking upon earth, their citizenship may be in heaven (cf. Phil. 3: 20).

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Therefore, the will of God which we pray may be done upon earth, is not that we should conform to the law, and live according to the grossness of its letter, but that we should endeavor to live by the gospel. And this is effected by a faith correct and free from error, and by a holy life, possessed of the sweet savor of every virtue, and proved by the testimony of good and noble conduct in every thing that is excellent.