לָ֣מָּה תִבְעֲט֗וּ בְּזִבְחִי֙ וּבְמִנְחָתִ֔י אֲשֶׁ֥ר צִוִּ֖יתִי מָע֑וֹן וַתְּכַבֵּ֤ד אֶת־בָּנֶ֙יךָ֙ מִמֶּ֔נִּי לְהַבְרִֽיאֲכֶ֗ם מֵרֵאשִׁ֛ית כָּל־מִנְחַ֥ת יִשְׂרָאֵ֖ל לְעַמִּֽי׃
Wherefore kick ye at My sacrifice and at Mine offering, which I have commanded in My habitation; and honourest thy sons above Me, to make yourselves fat with the chiefest of all the offerings of Israel My people?
Read Kabbalistic (mystical) interpretations of I Samuel 2:29: Zohar and classical Jewish mystical sources, free online.