St Anthony (c. 251–356) was not the first monk, but his Life, by St Athanasius, did much to promote the spread of monasticism, particularly in the West.
The Life is an extremely important source for ascetic spirituality. Here are a few extracts:
"Antony you must know was by descent an Egyptian: his parents were of good family and possessed considerable wealth, and as they were Christians he also was reared in the same Faith. In infancy he was brought up with his parents, knowing nought else but them and his home. But when he was grown and arrived at boyhood, and was advancing in years, he could not endure to learn letters, not caring to associate with other boys; but all his desire was, as it is written of Jacob, to live a plain man at home. With his parents he used to attend the Lord's House, and neither as a child was he idle nor when older did he despise them; but was both obedient to his father and mother and attentive to what was read, keeping in his heart what was profitable in what he heard. And though as a child brought up in moderate affluence, he did not trouble his parents for varied or luxurious fare, nor was this a source of pleasure to him; but was content simply with what he found nor sought anything further.
After the death of his father and mother he was left alone with one little sister: his age was about eighteen or twenty, and on him the care both of home and sister rested. Now it was not six months after the death of his parents, and going according to custom into the Lord's House, he communed with himself and reflected as he walked how the Apostles left all and followed the Saviour; and how they in the Acts sold their possessions and brought and laid them at the Apostles' feet for distribution to then eedy, and what and how great a hope was laid up for them in heaven. Pondering over these things he entered the church, and it happened the Gospel was being read, and he heard the Lord saying to the rich man, 'If thou wouldest be perfect, go and sell that thou hast and give to the poor; and come follow Me and thou shalt have treasure in heaven.' Antony, as though God had put him in mind of the Saints, and the passage had been read on his account, went out immediately from the church, and gave the possessions of his forefathers to the villagers--they were three hundred acres, productive and very fair --that they should be no more a clog upon himself and his sister. And all the rest that was movable he sold, and having got together much money he gave it to the poor, reserving a little however for his sister's sake.
And again as he went into the church, hearing the Lord say in the Gospel, ' be not anxious for the morrow,' he could stay no longer, but went out and gave those things also to the poor. Having committed his sister to known and faithful virgins, and put her into a convent to be brought up, he henceforth devoted himself outside his house to discipline, taking heed to himself and training himself with patience. For there were not yet so many monasteries in Egypt, and no monk at all knew of the distant desert; but all who wished to give heed to themselves practised the discipline in solitude near their own village. Now there was then in the next village an old man who had lived the life of a hermit from his youth up. Antony, after he had seen this man, imitated him in piety. And at first he began to abide in places out side the village: then if he heard of a good man anywhere, like the prudent bee, he went forth and sought him, nor turned back to his own palace until he had seen him; and he returned, having got from the good man as it were supplies for his journey in the way of virtue. So dwelling there at first, he confirmed his purpose not to return to the abode of his fathers nor to the remembrance of his kinsfolk; but to keep all his desire and energy for perfecting his discipline. He worked, however. with his hands, having heard, 'he who is idle let him not eat,' and part he spent on bread and part he gave to the needy. And he was constant in prayer, knowing that a man ought to pray in secret unceasingly. For he had given such heed to what was read that none of the things that were written fell from him to the ground, but he remembered all, and afterwards his memory served him for books."