As a general rule, decide whether a thing is permissible by the effect it produces within. Permit yourself what is constructive, but never what is destructive.
Faith is the sincere confession that God, Who is worshipped in the Trinity, Who created all things and provides for all, saves us who are fallen, through the power of the death on the Cross of the incarnate Son of God, by the grace of the Most Holy Spirit in His Holy Church. The beginnings of renewal, which are established in this life, will appear in all their glory in the future age, in a way that the mind cannot comprehend nor the tongue express.
Go, sell all that belongs to you and give it to the poor and taking up the cross, deny yourself; in this way you will be able to pray without distraction.
The origin of the Christian life is in arousal by grace. A person who has heeded this arousal is not then deprived of guidance by grace and communion with it at all times, as it persists through proper attention to it.
In no art do the artists judge the result of their work by the tools they use, but they await the work's completion and by it judge the art. Adopting such a practice with regard to food, not placing all your hope on fasting, but fasting moderately and according to the amount of your strength, strive toward mental activity. In this way you can avoid pride and will not spurn God's good works, sending up praises to God for everything.
In words of boastfulness and self-justification there always lie concealed contrariness and pride, from which God turns away. After sinning one ought immediately to 'flee.' But you say, where? To the calm haven of heartfelt repentance.
The simplest means for confining the will within its proper bounds lies in disposing children to do nothing without permission. Let them be eager to run to their parents and ask: May I do this or that? They should be persuaded by their own experience and that of others that to fulfill their own desires without asking is dangerous; they should be put in such a frame of mind that they even fear their own will.