וַיֹּ֨אמֶר שָׁא֜וּל אֶל־שְׁמוּאֵ֗ל אֲשֶׁ֤ר שָׁמַ֙עְתִּי֙ בְּק֣וֹל יְהוָ֔ה וָאֵלֵ֕ךְ בַּדֶּ֖רֶךְ אֲשֶׁר־שְׁלָחַ֣נִי יְהוָ֑ה וָאָבִ֗יא אֶת־אֲגַג֙ מֶ֣לֶךְ עֲמָלֵ֔ק וְאֶת־עֲמָלֵ֖ק הֶחֱרַֽמְתִּי׃
And Saul said unto Samuel: ‘Yea, I have hearkened to the voice of the LORD, and have gone the way which the LORD sent me, and have brought Agag the king of Amalek, and have utterly destroyed the Amalekites.
Find Mishnaic references to I Samuel 15:20: passages from the 63 tractates of the Mishnah that cite or discuss this verse, free.