Commentaire sur Les Proverbes 27:9

Oil and incense The scent of balsamum oil and the scent of incense cause the heart to rejoice.

and the sweet words of his friend more than one’s own counsel He whose friend draws him near with words is better than what his [own] soul advises him. Another explanation: and the sweetness of his friend who improves his deeds, that they should be sweet to the Holy One, blessed be He, is better for him than gratifying the desires of his heart.