Elder Ephraim of Philotheou and Arizona writes to a man asking whether or not he should become a monk. This letter was written in October 1957 when Elder Ephraim was on the Holy Mountain, two years before the repose of his Elder, St. Joseph the Hesychast.
My beloved brother in Christ..., may God bless and enlighten you along the unerring path of salvation. You asked me in your letter if you have the calling from the Lord to become a monk, lest you do something without Him having called you to monasticism and thus desert your responsibilities, etc.
My brother, "He who is able to accept it, let him accept it. Not everyone can accept this saying" (Matt 19:12,11). The characteristics of a calling are when a person sees within himself a keen desire, zeal, yearning, and a kind of eros towards monasticism. When he sees such things in himself, he is assured that God is definitely calling him to become a monk. Yet he is left completely free to choose by himself one or the other, but with the conviction that he has been given the aptitude and the calling, and if he wants, he may voluntarily, without coercion, embrace monasticism, which is also called the life of virginity.
This calling is due to the grace of God, which a person must not lay aside and quench. For if he lays it aside by remaining in the world for two or three years, it will surely be quenched, and then one's desire can no longer be kindled for such a lofty goal.
While such a person is still in the world, he needs to fast in accordance with his physical strength and with discernment, to keep vigil, to pray, to give alms, to guard himself from the things that defile his chaste disposition, to avoid bad company and talking with members of the opposite sex, to find time for stillness, to read, etc. All these things help to increase his desire for monasticism and keep it warm until the appropriate time comes to fulfill his desire, if, of course, he decides to; because as we said, a person is left completely free to choose, even though he has evidence of his calling from the characteristic signs.
Of course, when one has made a vow to God to become a monk, he is in a sense obligated to do so, just as the great Church Fathers say. When one is about to take a vow, one must think it over well, because breaking it will not have good results, since it is considered scorning God, to Whom he made the vow.
The life of virginity is lofty, for a person completely allows himself to please God without any obstacles, so that, in time, by working fully in the service of God, he may become holy in soul and body; he will be reborn; he will become a new man dedicated to Christ with the characteristics of the life in Christ.
My brother, whenever you want, you may come to the Holy Mountain, even as a pilgrim, and see things up close. If you like, you may stay as long as you want with us, or anywhere else. Our little house has two small cells: one for me, one for you. This way you will see better what you should do.
You will also hear spiritual words from experience, from my Elder, and—in a word—you will be enlightened to know what to do. In the beginning, the life in Christ has much toil and various temptations. But with time they abate and the spiritual consolation begins, such that when the grace of God visits, you will find yourself in a state of spiritual pleasure and delight.
-Elder Ephraim (2016). Counsels from the Holy Mountain: Selected from the Letters and Homilies of Elder Ephraim (2nd ed.). Saint Anthony's Greek Orthodox Monastery. p. 85-86.