Tafsiran Mazmur 15:3: Rashi & Radak

He did not slander with his tongue Ankuza in Old French, to accuse, as (in II Sam. 19:28) “And he slandered (וירגל) your servant.” This psalm is to inform us of the [proper] measure of piety.

He that slandereth not with his tongue: – In this verse he specifies certain prohibitions both as regards speech and deed; but it was not necessary for him to mention (such) of the heart, for he has already said and speaketh truth in his heart, and if his thoughts are truth and righteousness, then there is no evil in his thoughts. He says he slandereth not with his tongue, but does not enunciate the rest of the prohibitions concerning speech, such as: “Thou shalt not bear (false witness) against thy neighbour” (Exod. 20:16); “Thou shalt not revile the judges” (ibid. 22:27); and the like, for he says that which is true, and as a matter of course the others (follow); for from tale-bearing, although its subject-matter may be true, great harm proceeds. And so he says, and speaketh truth in his heart, for the truth that is harmful he does not utter, and that is tale-bearing.

neither did he take up reproach Rapporta in Old French, to report.

upon his kinsman If his kinsman committed a transgression for which he was punishable, he would punish him with justice, and he did not bear upon himself his reproach, that the reproacher should have an excuse to say, “So-and-so, your relative, committed such-and-such a sin, and you covered up for him.”