The kingdom of God is His rule and reign, His will being done on earth as it is in Heaven.
The phrase "Your will be done" refers to a continuing action.
We look for God's will to be done more and more on the earth.
In the Lord's Prayer, Jesus gives us authority to bring heaven on earth.
This same authority is presented differently in another place: "Assuredly, I say to you, whatever you bind on earth will be bound in heaven, and whatever you loose on earth will be loosed in heaven.
Again I say to you that if two of you agree on earth concerning anything that they ask, it will be done for them by My Father in heaven." Matthew 18:18,19
The Greek for "will be bound" actually means "will have already been bound."; likewise for "will be loosed."
By our binding and loosing, we are doing what has already been done in heaven.
We are causing the will of God to be done on earth as it is in heaven.
The power of agreement brings the things of heaven to earth.
When we agree on earth concerning anything we ask, it will be done for us by our Father in heaven.
When praying this, remember that, as one who has received the Lord Jesus Christ and has been born again, we are citizens of heaven, Philippians 3:20.
The Bible says that we are now seated with the Lord in the heavenlies, Ephesians 2:6.
This means that we do not bring heaven down to earth, we bring it forth!
The kingdom of God doesn't so much come to us as it does through us.
All of this is important in regards to healing because there is no sickness in heaven!
Sickness is not God's will in heaven, nor is it His will on earth.
When we pray, "Your will be done on earth as it is in heaven," we can apply that to healing and expect it to happen!