God's command to "pray without ceasing" is founded on the necessity we have of his grace to preserve the life of God in the soul, which can no more subsist one moment without it, than the body can without air.
Whether we think of; or speak to, God, whether we act or suffer for him, all is prayer, when we have no other object than his love, and the desire of pleasing him.
All that a Christian does, even in eating and sleeping, is prayer, when it is done in simplicity, according to the order of God, without either adding to or diminishing from it by his own choice.
Prayer continues in the desire of the heart, though the understanding be employed on outward things.
In souls filled with love, the desire to please God is a continual prayer.
As the furious hate which the devil bears us is termed the roaring of a lion, so our vehement love may be termed crying after God.
God only requires of his adult children, that their hearts be truly purified, and that they offer him continually the wishes and vows that naturally spring from perfect love. For these desires, being the genuine fruits of love, are the most perfect prayers that can spring from it.
From "A Plain Account of Christian Perfection", as believed and taught by the Reverend Mr. John Wesley, from the year 1725, to the year 1777.
And, of course, the Wesleyan Covenant Prayer:
I am no longer my own but yours,
Put me to what you will
Put me to doing, put me to suffering.
Let me be employed for you or laid aside for you.
Let me be full, let me be empty.
Let me have all things, let me have nothing.
I freely and wholeheartedly yield all things to Your pleasure and disposal
And now glorious and blessed God, Father, Son and Holy Spirit,
You are mine and I am yours. So be it.
And this covenant now made on earth, let it be satisfied in heaven.