Every moral & thinking Jew has asked questions about certain mitzvot which don't seem to "jive" with the morality of God & the Torah itself! Rav Kook, as usual, bravely deals with these issues, & explains that "eternity" means that the Torah also had to be relevant to the primitive world in which it was given 3,300 yrs. ago. He differentiates between some actions, like slavery & bigamy, that had to be "allowed" temporarily in the ancient reality, but were never obligated. Nevertheless, 2 obligations (!) which seem "immoral" are regarding Amalek (killing & remembering-Zachor), & conquering the Land of Israel. But upon a closer look, they aren't immoral at all! When we lack prophets & Sanhedrin, the God Who runs History solves many problems!