As the Holy Trinity, our God is One Being, although Three Persons, so, likewise, we ourselves must be one. As our God is indivisible, we also must be indivisible, as though we were one man, one mind, one will, one heart, one goodness, without the smallest admixture of malice - in a word, one pure love, as God is Love. That they may be one, even as We are One (John 17:22).
John of KronstadtAvoid duplicity, that is, do not let your heart be divided between attachment to God and attachment to earthly things, 'You cannot serve God and mammon' (Mt. 6:24); cling to God alone, put your trust in Him alone; for the Devil, by inciting us to duplicity, seeks himself to gain possession of our heart, which is single and indivisible.
John of KronstadtIn prayer and in every work of your life avoid suspicious ness, doubt and diabolical imaginations. Let your spiritual eye be single, in order that the whole body of your prayer, of your works and of your life may be light.
John of KronstadtChrist taught us truth; the Devil teaches us falsehood, and strives in every way to contradict every truth; devising various calumnies against it.
John of KronstadtWhen you are subjected to the malicious and furious violence of the passions, and to the harassments of the Devil, during the fulfillment of various works for God, accept these sufferings as sufferings for the name of Christ, and rejoice in your sufferings, thanking God; for the Devil is preparing you, without knowing it himself, the most shining crowns from the Lord.
John of KronstadtDo not be irritated either with those who sin or those who offend; do not have a passion for noticing every sin in your neighbour, and for judging him, as we are in the habit of doing. Everyone shall give an answer to God for himself. Everyone has a conscience; everyone hears God's Word, and knows God's Will either from books or from conversation with other people. Especially do not look with evil intention upon the sins of your elders, which do not regard you; "to his own master he standeth or falleth." Correct your own sins, amend your own life.
John of Kronstadt