Therefore, guard your memory well, so that it does not present you with its own cares.
And continuously urge yourself to remain aware in Whose presence it is standing, because it is very natural for the mind to be easily carried away by memory during the time of prayer.
The attention paid by the mind that seeks prayer will find prayer, because prayer follows attention more than anything else.
Let us therefore ensure that we willingly strive to acquire attention.
At times, by remaining standing during prayer, you can immediately concentrate and pray well; at other times, you may strive very hard, but not achieve your purpose.
This occurs, so that you may ask for prayer with greater zeal; and after acquiring it, to have it as your inalienable achievement.
[...] A true prayer is said by the one who always offers his first thought as a sacrifice to God.
Do not pray for your desires to be realized, because they certainly do not agree with the will of God;
but rather, as you were taught, say in your prayer: “Let Your Will be done” (Matt 6:10), and for every single thing, you should likewise ask God that His Will be done, because He wants whatever is best and beneficial for your soul.
I have often asked God through prayer for something I thought to be good. And I insisted illogically on asking for it, thus violating the divine will.
I would not let God provide whatever He knew would be to my benefit.
And so, having received what I had asked for, I afterwards felt very sorry that I had not asked that His Will be done, because things did not turn out as I had thought they would.
What is benevolent, if not God? Let us therefore entrust all our needs with Him and everything will go well, as the benevolent One definitely also bestows beneficial gifts.
In your prayer, ask only for the justice and the Kingdom of God – in other words, virtue and divine knowledge – and all the rest will then be added to you.
Entrust the needs of your body to God, and that will reveal to Him that you also entrust the needs of your spirit.
Nilus the Ascetic of Sinai (d. c.430): On Prayer, trans. Holy Monastery of the Paraklete Oropos, Attica (Greece).