Sating one's hatred under cover of correction

"Third, he should strive in all charity to correct the sins of others, and this is indicated by the words judging without dissimulation, lest he should purpose to sate his hatred under cover of correction."

"Tertio requiritur ut caritative emendare peccata satagat, et hoc est quod dicit, iudicans sine simulatione, ne scilicet, correctionem praetendens, odium intendat explere."

     St. Thomas Aquinas, Summa theologiae II-II.45.6.ad 3.