וְיוֹאָב֙ וַאֲבִישַׁ֣י אָחִ֔יו הָרְג֖וּ לְאַבְנֵ֑ר עַל֩ אֲשֶׁ֨ר הֵמִ֜ית אֶת־עֲשָׂהאֵ֧ל אֲחִיהֶ֛ם בְּגִבְע֖וֹן בַּמִּלְחָמָֽה׃ (פ)
Così Ioab e Abishai suo fratello uccisero Abner, perché aveva ucciso Asael loro fratello a Gabaon nella battaglia.
Ibn Ezra
love to your fellowman as yourself Many people have said that the lamed is superfluous, like the lamed in “they killed Avner” [II Samuel 3:30] [literally: they killed to Avner]. In my opinion, however, it contributes to the verse’s meaning. One must love the good that pertains to one’s fellowman as much as one loves the good that pertains to oneself.