Intemperance and attachment to things cause torrents of passions to flood the soil of the heart and deposit there all the mud and filth of thoughts, thus confusing the mind, darkening the heart and weighing down the body. In the heart and the soul they produce negligence, darkness and death and deprive them of the feeling and disposition natural to them.
Conscience in men is nothing else but the voice of the omnipresent God moving in the hearts of men, as He Who alone Is and has created everything, the Lord knows all as Himself - all the thoughts, desires, intentions, words, and works of men, present, past, and future. However far in front I may let my thoughts, my imagination, run He is there before me and I ever inevitably finish my course in Him, ever having Him as the witness of my ways. 'His eyes are open upon all the ways of the sons of men' (Jer 32:19). 'Whither shall I go from Thy Spirit, or whither shall I flee from Thy presence?' (Ps 139:7).
It is up to us now to either bury our conscience under the ground, or to have it shine forth and illuminate us if we obey it. When our conscience says to us, 'Do this,' and we treat it with contempt, or it says it again and we refuse, then we are trampling it down, burying it under ground. Thus, it cannot speak to us clearly because of the weight upon it.
According to the teaching of the Fathers, any impression which, touching the heart, fills it with a great irritation, must come from the region of passions. Therefore impulses which spring from the heart should not be followed at once, but only after careful examination and fervent prayer. God preserve us from a blind heart! It is well known that passions do blind the heart and screen the shining sun of the mind that we should all strive to gaze at.
In the heart is the will; in the heart is love; in the heart is the mind--in the heart is the image of the divine Trinity. The heart is the home of the Father, the altar of the Son and the workshop of the Holy Spirit. God wants our hearts: Son, give Me thy heart. Oh, my brother, above and beyond all else that you keep safe, guard your heart. Let the mountains be overthrown and the seas dried up; let friends forsake you and riches betray you; let your body be eaten by worms; let the world pour on you all the scorn of which it is capable--and do not fear. Only guard your heart; guard it and make it cleave to the Lord; give it into His keeping. Life flows from the heart; but whence comes this life in the heart, unless it is the abode of the breath of the Lord and Source of life-God? Oh, my brother, the Spirit of God Himself can, when He so desires, dwell in the human heart. He not only can, but wills to do so. Only, He waits for you to prepare your heart for Him; to make it into a temple, for God the Holy Spirit only lives in a temple. As a snake protects its head, so, my son, guard your heart. For the life that comes from the living God enters into it and flows forth from it.
No man, wise in his own opinion, because he has studied all the sciences and is learned in external wisdom, will ever penetrate God's mysteries or see them unless he first humbles himself and becomes foolish in his heart, repudiating his self-opinion together with his acquirements of learning. For a man who acts thus and follows with undaunted faith those who are wise in things Divine, is guided by them and with them enters into the city of the living God, and, taught and enlightened by the Holy Spirit, sees and knows things which no one else can see or know. Thus he becomes taught of God.
He who stands by a fire is warmed by it, and he who turns to the Lord with his mind and heart is warmed by the fervor of His love, and himself begins to return a warm disposition towards Him...The love of God is shed abroad in our hearts... (Rom. 5:5).
When God, using our conscience, calls us to righteousness and yet our self-will opposes Him, He respects our freedom and lets our own will be done; but then, alas, our minds grow dull, our will slack, and we commit iniquities without number. On the other hand, the fruits of the spirit are soon granted to them who follow the commandments of Christ our Lord.
In Christianity truth is not a philosophical concept nor is it a theory, a teaching, or a system, but rather, it is the living theanthropic hypostasis - the historical Jesus Christ (John 14:6). Before Christ men could only conjecture about the Truth since they did not possess it. With Christ as the incarnate divine Logos the eternally complete divine Truth enters into the world. For this reason the Gospel says: 'Truth came by Jesus Christ' (John 1:17).
Not every man is wakened to wonder by what is said spiritually and has great power concealed in it. A word concerning virtue has need of a heart unbusied with the earth and its converse.
He who chooses maltreatment and dishonor for the sake of truth is walking on the apostolic path; he has taken up the cross and is bound in chains (cf. Mt 16:24). But when he tries to concentrate his attention on the heart without accepting these two, his intellect wanders from the path and he falls into the temptations and snares of the devil.