7 “The righteous One shall amend me in mercy, and convict me”. Behold the sinner confessing. He desires to be amended in mercy, rather than praised deceitfully....“Shall convict me,” but “in mercy:” shall convict, yet hates not: yea, shall all the more convict, because He hates not. And why does he therefore give thanks? Because, “rebuke a wise man, and he will love you.” “The righteous One shall amend me.” Because He persecutes you? God forbid. He requires rather amending himself, who amends in hate. Wherefore then does He amend? “In mercy. And shall convict me.” Wherein? “In mercy. For the oil of a sinner shall not enrich my head.” My head shall not grow by flattery. Undue praise is flattery: undue praise of a flatterer is “the oil of a sinner.” Therefore men too, when they have mocked any one with false praise, say, “I have anointed his head.” Love then to be “convicted by the righteous One in mercy;” love not to be praised by a sinner in mockery. Have oil in yourselves, and you shall not seek the “oil of a sinner.”...
Source: The Enarrations, or Expositions, on the Psalms (New Advent)