God shows mercy on him, yet you judge him?

Patristic reading
If we have love, with sympathy and compassion, we shall not see our neighbour's faults, as it says that

Man can know nothing about the judgement of God. Only God is the One who understands and can judge everything as only He knows. Indeed, it happens that a brother may do something out of simplicity and this simplicity may please God more than all your acts. However, you sit there judging him and punishing your soul? Even if he acted improperly, how do you know how much he struggled and how much blood he sweated before he acted? His offence may almost be found justified before God, since God sees bis labour and sorrow before he acted and shows mercy on him and forgives him. Thus, God shows mercy on him but yet you judge him and lose your soul. How do you know how many tears he shed before God about it? You know about the sin but not about the repentance... How do we undergo these things, unless it is because wc do not have love? If we have love, with sympathy and compassion, we shall not see our neighbour's faults, as it says that, "Love will cover a multitude of sins" (1 Pet. 4:8). Again, it says that, "Love thinks no evil, bears all things", and so on (1 Cor. 13:5-7). As I have said, if we have love, this love should cover the defects of men. I wonder if the saints are blind and they can not see sins, because who hates sin as much as the saints? Yet, in spite of that they do not hate the sinner. They do not judge or dislike him but suffer with him, admonish him, offer him consolation and healing like a sick member. They do everything to save the sinner.

Dorotheos of Gaza, Practical Teaching on the Christian Life VI,74.76