9 By this means men are deceived, so that they either do not undertake, or rashly attempt, a better life; because, when they choose to praise, they praise without mention of the evil that is mixed with the good: and those who choose to blame, do so with so envious and perverse a mind, as to shut their eyes to the good, and exaggerate only the evils which either actually exist there, or are imagined. Thus it happens, that when any profession has been ill, that is, incautiously, praised, if it has invited men by its own reputation, they who betake themselves there discover some such as they did not believe to be there; and offended by the wicked recoil from the good. Brethren, apply this teaching to your life, and hear in such a manner that you may live. The Church of God, to speak generally, is magnified: Christians, and Christians alone, are called great, the Catholic (Church) is magnified; all love each other; each and all do all they can for one another; they give themselves up to prayers, fastings, hymns; throughout the whole world, with peaceful unanimity God is praised. Some one perhaps hears this, who is ignorant that nothing is said of the wicked who are mingled with them; he comes, invited by these praises, finds bad men mixed with them, who were not mentioned to him before he came; he is offended by false Christians, he flies from true Christians. Again, men who hate and slander them, precipitately blame them: asking, what sort of men are Christians? Who are Christians? Covetous men, usurers. Are not the very persons who fill the Churches on holidays the same who during the games and other spectacles fill the theatres and amphitheatres? They are drunken, gluttonous, envious, slanderers of each other. There are such, but not such only. And this slanderer in his blindness says nothing of the good: and that praiser in his want of caution is silent about the bad....Thus also in that common life of brethren, which exists in a monastery: great and holy men live therein, with daily hymns, prayers, praises of God; their occupation is reading; they labour with their own hands, and by this means support themselves; they seek nothing covetously; whatever is brought in for them by pious brethren, they use with contentedness and charity; no one claims as his own what another has not; all love, all forbear one another mutually. You have praised them; you have praised; he who knows not what is going on within, who knows not how, when the wind enters, ships even in harbour dash against one another, enters as if in hope of security, expecting to find no man to forbear; he finds there evil brethren, who could not have been found evil, if they had not been admitted (and they must be at first tolerated, lest they should perchance reform; nor can they easily be excluded, unless they have first been endured): and becomes himself impatient beyond endurance. Who asked me here? I thought that love was here. And irritated by the perversity of some few men, since he has not persevered in fulfilling his vow, he becomes a deserter of so holy a design, and guilty of a vow he has never discharged. And then, when he has gone forth himself too, he also becomes a reproacher, and a slanderer; and records those things only (sometimes real), which he asserts that he could not have endured. But the real troubles of the wicked ought to be endured for the society of the good. The Scripture says unto him: “Woe unto those that have lost patience.” And what is more, he belches abroad the evil savour of his indignation, as a means to deter them who are about to enter; because, when he had entered himself, he could not persevere. Of what sort are they? Envious, quarrelsome, men who forbear no man, covetous; saying, He did this there, and he did that there. Wicked one, why are you silent about the good! You say enough of those whom you could not endure: you say nothing of those who endured your wickedness....
10. “O serve the Lord with gladness”: he addresses you, whoever you are who endure all things in love, and rejoice in hope. “Serve the Lord,” not in the bitterness of murmuring, but in the “gladness of love.” “Come before His presence with rejoicing.” It is easy to rejoice outwardly: rejoice before the presence of God. Let not the tongue be too joyful: let the conscience be joyful. “Come before His presence with a song.”
11. “Be sure that the Lord He is God”. Who knows not that the Lord, He is God? But He speaks of the Lord, whom men thought not God: “Be sure that the Lord He is God.” Let not that Lord become vile in your sight: you have crucified Him, scourged Him, spit upon Him, crowned Him with thorns, clothed Him in a dress of infamy, hung Him upon the Cross, pierced Him with nails, wounded Him with a spear, placed guards at His tomb; He is God. “It is He that has made us, and not we ourselves.” It is He that has made us: “and without Him was not anything made that was made.” What reason have ye for exultation, what reason have ye for pride? Another made you; the Same who made you, suffers from you. But ye extol yourselves, and glory in yourselves, as if you were created by yourselves. It is good for you that He who made you, make you perfect....“We are His people, and the sheep of His pasture.” Sheep and one sheep. These sheep are one sheep: and how loving a Shepherd we have! He left the ninety and nine, and descended to seek the one, He brings it back on His own shoulders ransomed by His own blood. That Shepherd dies without fear for the sheep, who on His resurrection regains His sheep.
12. “Enter into His gates with confession”. At the gates is the beginning: begin with confession. Thence is the Psalm entitled, “A Psalm of Confession:” there be joyful. Confess that you were not made by yourselves, praise Him by whom you were made. Let your good come from Him, in departing from whom you have caused your evil. “Enter into His gates with confession.” Let the flock enter into the gates: let it not remain outside, a prey for wolves. And how is it to enter? “With confession.” Let the gate, that is, the commencement for you, be confession. Whence it is said in another Psalm, “Begin unto the Lord with confession.” What he there calls “Begin,” here he calls “Gates.” “Enter into His gates in confession.” What? And when we have entered, shall we not still confess? Always confess Him: you have always what to confess for. It is hard in this life for a man to be so far changed, that no cause for censure be discoverable in him: you must needs blame yourself, lest He who shall condemn blame you. Therefore even when you have entered His courts, then also confess. When will there be no longer confession of sins? In that rest, in that likeness to the Angels. But consider what I have said: there will there be no confession of sins. I said not, there will be no confession: for there will be confession of praise. You will ever confess, that He is God, thou a creature; that He is your Protector, yourself protected. In Him you shall be as it were hid. “Go into His courts with hymns; and confess unto Him.” Confess in the gates; and when you have entered the courts, confess with hymns. Hymn are praises. Blame yourself, when you are entering; when you have entered, praise Him. “Open me the gates of righteousness,” he says in another Psalm, “that I may go into them, and confess unto the Lord.” Did he say, when I have entered, I will no longer confess? Even after his entrance, he will confess. For what sins did our Lord Jesus Christ confess, when He said, “I confess unto You, O Father”? He confessed in praising Him, not in accusing Himself. “Speak good of His Name.”
Source: The Enarrations, or Expositions, on the Psalms (New Advent)