"Prayer without Ceasing" is necessary for all Christians St Gregory Palamas
“Let no one think, my brother Christians, that it is the duty only of priests and monks to pray without ceasing, and not of laymen. No, no; it is the duty of all of us Christians to remain always in prayer.
As first it may appear very difficult to you, but be assured, as it were from Almighty God, that this very name of our Lord Jesus Christ, constantly invoked by you, will help you to overcome all difficulties, and in the course of time you will become used to this practice and will taste how sweet is the name of the Lord. Then you will learn by experience that this practice is not impossible and not difficult, but both possible and easy.
This is why St. Paul, who knew better than we the great good which such prayer would bring, commanded us to pray without ceasing. He would not have imposed this obligation upon us if it were extremely difficult and impossible, for he knew beforehand that in such case, having no possibility of fulfilling it, we would inevitably prove to be disobedient and would transgress his commandment, thus incurring blame and condemnation. The Apostle could have had no such intention.”
St Gregory Palamas, from "Early Fathers From the Philokalia," (London: Faber and Faber, Ltd., 1981)
“Likewise the Spirit helps us in our weakness; for we do not know how to pray as we ought, but the Spirit himself intercedes for us with sighs too deep for words. And he who searches the hearts of men knows what is the mind of the Spirit, because the Spirit intercedes for the saints according to the will of God.” (Rom 8: 26-27).
“ Watch therefore, and pray always that you may be counted worthy to escape all these things that will come to pass, and to stand before the Son of Man.” Luke 21:36
“O my God, teach my heart where and how to seek You, where and how to find You. You are my God and You are my all and I have never seen You.
You have made me and remade me,You have bestowed on me all the good things I possess, Still I do not know You.
I have not yet done that for which I was made.
Teach me to seek You. I cannot seek You unless You teach me or find You unless You show Yourself to me.
Let me seek You in my desire, let me desire You in my seeking.
Let me find You by loving You, let me love You when I find You. Amen”
St Anselm of Canterbury
Paul's Prayer Ephesians 3:13-21
"For this reason I bow my knees to the Father of our Lord Jesus Christ, from whom the whole family in heaven and earth is named, that He would grant you, according to the riches of His glory, to be strengthened with might through His Spirit in the inner man, that Christ may dwell in your hearts through faith; that you, being rooted and grounded in love, may be able to comprehend with all the saints what is the width and length and depth and height— to know the love of Christ which passes knowledge; that you may be filled with all the fullness of God.
Now to Him who is able to do exceedingly abundantly above all that we ask or think, according to the power that works in us, to Him be glory in the church by Christ Jesus to all generations, forever and ever.