In Christopher Marlowe's The Tragical History of Doctor Faustus, why did Faustus begin to believe that human salvation was impossible?

Faustus first began to believe that human salvation was impossible because:
[he felt God always hate him because of his sins and punish him]
[he felt he had committed too many sins and so his soul could not be saved]
[he read the scripture and saw that all human beings sin and are D word]
[he felt ashamed to ask God for mercy and suffered from depression]

In addition, he had:
[been misled by Mephastophills, who caused him to misread the scriptures]
[offered the blood of children to gain his power and felt his sin was unforgivable]
[been disgusted by the pettiness of human nature]
[been tricked into practicing witchcraft by Valdes and Cornelius and felt it D word his soul]