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With regard to the king’s rights, the Sages engaged in a dispute: Rav Yehuda says that Shmuel says: Concerning all the actions that are stated in the biblical passage about the king (see I Samuel 8:11–17), it is permitted for a king to perform them. Rav says: This biblical passage was stated only in order to threaten the Jewish people, so that they would accept the king’s sovereignty with reverence, as it is stated: “You shall set a king over you” (Deuteronomy 17:15), meaning, it is necessary that his fear should be upon you. But the king is not actually permitted to perform the actions stated there. The Gemara comments that this dispute is parallel to a dispute between tanna’im, as it is taught in a baraita: Rabbi Yosei says: Concerning all the actions that are stated in the biblical passage about the king, it is permitted for a king to perform them. Rabbi Yehuda says: This biblical passage was stated only in order to threaten the Jewish people, as it is stated: “You shall set a king over you” (Deuteronomy 17:15), meaning, it is necessary that his fear should be upon you. The baraita continues: And so would Rabbi Yehuda say: Three mitzvot were commanded to the Jewish people upon their entrance into Eretz Yisrael, which apply only in Eretz Yisrael: They were commanded to establish a king for themselves (see Deuteronomy 17:14–15), and to cut off the seed of Amalek in war (see Deuteronomy 25:17–19), and to build the Chosen House, i.e., the Temple, in Jerusalem (see Deuteronomy 12:10–12). The baraita continues: Rabbi Nehorai says: This biblical passage about appointing a king was stated only in response to the Jewish people’s complaint, as it is stated: “When you come unto the land that the Lord your God gives you, and shall possess it, and shall dwell therein, and shall say: I will set a king over me, like all the nations that are around me” (Deuteronomy 17:14). The verse indicates that appointing a king is not a mitzva and that when Samuel spoke to them, he intended to frighten them so that they might regret their complaint and retract their request for a king. It is taught in a baraita: Rabbi Eliezer says: The elders of Samuel’s generation asked appropriately, as it is stated: “Give us a king to judge us” (I Samuel 8:6), since they wanted a steady leader in place of Samuel. But the ignoramuses among them ruined it, as it is stated: “But the people refused to heed the voice of Samuel; and they said: No, but there shall be a king over us, that we also may be like all the nations, and that our king may judge us, and emerge before us, and fight our battles” (I Samuel 8:19–20).

The appointment of a king should precede the war against Amalek. This is evident from Samuel's charge to King Saul (I Samuel 15: l-3): 'God sent me to anoint you as king ... Now, go and smite Amalek.'
Amalek's seed should be annihilated before the construction of the Temple, as II Samuel 7:1-2 states: 'And it came to pass, when the king dwelled in his palace, and God gave him peace from all his enemies who surrounded him, the king said to Nathan, the prophet: 'Look! I am dwelling in a house of cedar, ... but the ark of God dwells within curtains.'
Since it is a mitzvah to appoint a king, why was God displeased with the people's request of a king from Samuel? Because they made their request in a spirit of complaint. Rather than seeking to fulfill the mitzvah of appointing a king, they were simply intent on rejecting the Prophet Samuel as implied by God's reply to him (I Samuel 8:7 : 'It is not you, but Me they have rejected.'