When an archer desires to shoot his arrows successfully, he first takes great pains over his posture and aligns himself accurately with his mark. It should be the same for you who are about to shoot the head of the wicked devil. Let us be concerned first for the good order of sensations and then for the good posture of inner thoughts.
Nothing that happens to us is contrary to the will of Providence, and everything that is sent us by God is for our good and the salvation of our soul. Even if it does not seem helpful at the moment, we shall understand later on that it was willed so by God, and that it is not what we ourselves wish that is always useful to us. God sends trials out of his Mercy, so that after we have suffered, we may be crowned by Him. Without temptation it is impossible to receive a crown. This is why we should thank God for these sufferings, as out Benefactor and Savior.
If you believe in a Divine Providence which determines the earthly fate of everyone and the way by which he is to be saved, you must also believe that the disposition of your life is the most suitable for you in working out your salvation.
When you intend to do something and see that your thought is perturbed, and if after invoking God's Name it remains perturbed even by a hair's breadth, know from this that the action you mean to commit is from the evil one and refrain from commiting it. For nothing done with perturbation is pleasing to God.
When tested by some trial you should try to find out not why or through whom it came, but only how to endure it gratefully, without distress or rancor.
In answer to your question as to what constitutes a happy life, whether splendor, fame and wealth, or a quiet, peaceful, family life, I will say that I agree with the latter, but will add the following: A life lived in humility and with an irreproachable conscience brings peace, tranquility, and true happiness. But wealth, honor, glory and exalted position often serve as the cause of a multitude of sins, and such happiness is not one on which to rely.
Let us avail ourselves of the example of that holy staretz who used to say: 'Depart, evil one; come, beloved!' Once a brother who overheard his words and supposed that the staretz was speaking to another man asked him 'With whom are you conversing, father?' And the staretz answered: 'I am driving away evil thoughts and calling the good ones to my side.' And so, if we are tempted, let us use the words of that staretz, or others like them.
Observe your thoughts, and beware of what you have in your heart and your spirit, knowing that the demons put ideas into you so as to corrupt your soul by making it think of that which is not right, in order to turn your spirit from the consideration of your sins and of God.
Knowing the exact nature of everything, God permits each person to be tested according to his strength. As St. Paul puts it: 'God is to be trusted not to let you be tried beyond your strength, but with the trial He will provide a way out, so that you are able to bear it' (1 Cor. 10:13).