וַיֹּ֤אמֶר אֵלָיו֙ שְׁמוּאֵ֔ל קָרַ֨ע יְהוָ֜ה אֶֽת־מַמְלְכ֧וּת יִשְׂרָאֵ֛ל מֵעָלֶ֖יךָ הַיּ֑וֹם וּנְתָנָ֕הּ לְרֵעֲךָ֖ הַטּ֥וֹב מִמֶּֽךָּ׃
Da sprach Samuel zu ihm. So hat heute weggerissen der Herr das Königtum Israel von dir; er hat es gegeben deinem Genossen, der besser ist denn du.
Rashi
To your fellow, to Dovid. But during his lifetime, he [Shmuel] did not mention his name [Dovid] to him, only 'and He gave it to your fellow who is better than you'23Above 15:28. because he feared that he [Shaul], might kill him,24Now however, that Shmuel was in the עוֹלָם הָאֶמֶת [=World of Truth] there was nothing to fear speaking the complete truth. because he had anointed him [Dovid] as king.
Or HaChaim
אבידן בן גדעוני. This is an allusion to King Saul who was referred to by David as אבי, "my father" (compare Samuel I 24,11) when David had cut off Saul's mantle instead of killing him. Saul had deserved to be killed seeing that G'd had already judged him, דן, and told him he had forfeited his crown (Samuel I 15). There is also an allusion in this name to Mordechai who destroyed the seed of Amalek. The word בן גדעוני means that he (David) was the one on whose account Saul's kingdom had been taken from him.