7 But what is necessary at the present time for those who have righteousness? That which is read in that psalm: “Until righteousness is turned into judgment, and they that have it are upright of heart.” You ask, perhaps, who are the upright in heart? We find in Scripture those to be upright in heart who bear the evils of the world, and do not accuse God. See, brethren, an uncommon thing is that which I speak of. For I know not how it is that, when any evil befalls a man, he runs to accuse God, when he ought to accuse himself.
When you get any good, you praise yourself; when you suffer any evil, you accuse God. This is then the crooked heart, not the upright. When you are cured of this distorting and perversity, what you used to do will be turned into the contrary. For what did you use to do before? You praised yourself in the good things of God, and accused God in your own evil things; with your heart converted and made right, you will praise God in His good things, and accuse yourself in your own evil things.
These are the upright in heart. In short, that man, who was not yet right in heart when the success of the wicked and the distress of the good grieved him, says, when he is corrected: “How good is the God of Israel to the upright in heart! But as for me,” when I was not right in heart, “my feet were almost gone; my steps had nearly slipped.” Why? “Because I was envious at sinners, beholding the peace of sinners.” I saw, says he, the wicked prosperous, and I was displeased at God; for I did wish that God should not permit the wicked to be happy.
Let man understand: God never does permit this; but a bad man is thought to be happy, for this reason, because men are ignorant of what happiness is. Let us then be right in heart: the time of our glory is not yet come. Let it be told to the lovers of this world, such as the brethren of the Lord were, “your time is always ready;” our time “is not yet come.” For let us, too, dare to say this. And since we are the body of our Lord Jesus Christ, since we are His members, since we joyfully acknowledge our head, let us say it without hesitation; since, for our sakes, He deigned also Himself to say this.
And when the lovers of this world revile us, let us say to them, “Your time is always ready; our time is not yet come.” For the apostle has said to us, “For you are dead, and your life is hid with Christ in God.” When will our time come? “When Christ,” says he, “your life shall appear, then shall you also appear with Him in glory.”
Source: Tractates on the Gospel of John (New Advent)