Another time Rabbi Shimon was sitting in Rebbe’s presence when he finished a section of the Book of Psalms (one of the five books that Tehillim is divided into). Rebbe said, “How neat is this writing!” Rabbi Shimon replied, “I did not write it; Yehudah Chayata wrote it.” Rebbe rebuked him by saying, “Stay away from this lashon hara.”
The Gemora asks: In the first case (by the tied document), one can understand Rebbe’s rebuke, since there was lashon hara involved; what lashon hara, however, was there in this case?
The Gemora answers: It is based upon the teaching of Rav Dimi, for Rav Dimi, the brother of Rav Safra, taught a braisa: A man should never speak in praise of his friend, because by mentioning his praise, he will come to mention his faults as well.
The Gemora in Gittin (67a) relates that Issi ben Yehudah used to specify the praiseworthy merits of the various Sages.
The Chidah challenges this from our Gemora, which rules that one should never speak in praise of his friend, because by mentioning his praise, he will come to mention his faults as well!?
He initially answers that Issi ben Yehudah specified their merits after their death; it would then be permitted, for there was no concern that he would talk about their faults after their deaths.
He retracts from this answer, for it is evident from the Avod d’Rabbi Nassan that Issi ben Yehudah spoke about their praises even during their lifetime!
It would seem that the Chidah’s question can be answered according to the words of the Rashbam here. He writes that a person should never speak excessively in praise of his friend, because by mentioning his praise, he will come to mention his faults as well. Apparently, it is only prohibited if one offers excessive praise; this will lead to the listener or the speaker interjecting that the person does possess some faults as well. Issi ben Yehudah, however, was not exaggerating at all when specifying the merits of those Sages.
The Maharsha challenges this explanation, for it does not seem from our Gemora that Rabbi Shimon was excessively praising Yehudah Chayata; he was merely stating that it was he who wrote that book of Tehillim, and that it was a neat handwriting.
The Rambam is of the opinion that this prohibition applies only in public, for there are bound to be enemies of the subject of the praise in the crowd, and they will almost certainly begin to talk disparagingly about him. In private, however, this prohibition would not apply.