If the kingdom of God is within us and that is a kingdom of justice, of peace, and of joy then whoever remains with these virtues is certainly in the kingdom of God. By contrast, all who deal in unrighteousness, in discord, and in death-bearing gloom have taken their stand in the kingdom of the devil, in hell and in lifelessness. It is by these tokens that the kingdom of God or of the devil is recognized.
John CassianThe thief who received the kingdom of heaven, though not as the reward of virtue, is a true witness to the fact that salvation is ours through the grace and mercy of God.
John CassianNo just man suffices unto himself for the winning of justification. The divine mercy must always hold out a hand to his footsteps as they falter and almost stumble, and this is so because the weakness of his free will may cause him to lose balance, and if he falls he may perish forever.
John CassianEverything we do, our every objective, must be undertaken for the sake of... purity of heart... we must practice the reading of the Scripture, together with all the other virtuous activities... to hold our hearts free of the harm of every dangerous passion and in order to rise step by step to the high point of love.
John Cassian