This is done by giving up all of their property and in many cases becoming a simple beggar. In addition to the giving of their belongings, a self-purification of their soul is also necessary. By suppressing and getting rid of evil desires of greed, jealousy, hatred and other sins of the body and mind they advance them selves closer to God and to becoming a mystic. This is the most difficult part in becoming a mystic. To drive away emotions that humans are born with and have lived by is very difficult. For this reason so many mystics use physical abuse to rid themselves of such evil thoughts as well as simply denying things the body would want. For example fasting is one way mystics might punish themselves for evil thought or actions. It's a self-conquest over one's own body. When earthly goods are no longer a desire the first stage of purgation is completed.
The next step in becoming a mystic is called "illumination". This happens when the body has been satisfied and the mind needs to more fully accept and believe in God's values and love. When a full acceptance of God takes place the individual will reach the final plateau of "Unity" where the mystic is surrounded by God's love and has a clear understanding of Him.
In medieval mysticism the body served as the central conflict from reaching God. In order to live a more holy and Christ-like life, the body had to be denied pleasure and punished when wrong. When a mystic had conquered his own body he could experience God first-hand. This was the case for mystics such as Hildegard of Bingen, St. Bernard of Clairvaux, and St. Francis.
Part II, #4.
St. Francis was born in 1181 in Assisi, Italy to a wealthy merchant. In his early years St. Francis lived a life of popularity, excitement and comfort and planned to follow in his father's footsteps. In 1201he enlisted in the military and was sent to battle in Perugia. St. Francis was captured and held in Perugia for over a year and it was there that Francis began to turn towards religion.