Judaism
Christianity was originally a sect of Second Temple Judaism, but the two religions diverged in the first century. The differences between Christianity and Judaism originally centered on whether Jesus was the Jewish Messiah but eventually became irreconcilable. Major differences between the two faiths include the nature of the Messiah, of atonement and sin, the status of God's commandments to Israel, and perhaps most significantly of the nature of God himself. Due to these differences, Judaism traditionally regards Christianity as Shituf or worship of the God of Israel which is not monotheistic. Christianity has traditionally regarded Judaism as obsolete with the invention of Christianity and Jews as a people replaced by the Church, though a Christian belief in dual-covenant theology emerged as a phenomenon following Christian reflection on how their theology influenced the Nazi Holocaust.
Hashkafa
With the rise of Jewish philosophy and great Jewish thinkers, various sects of Orthodox Judaism have developed throughout history, each with their distinct hashkafa. While certain meta-principles are present in all sects—primarily the ones precisely demarcated in the Torah and Talmud, others have been the subject of much disagreement, especially those that deal with pertinent and pressing issues. Despite the vast differences between Hasidism and Modern Orthodoxy, both are still considered legitimate. The idea that there can be more than one correct understanding is deeply rooted in Jewish texts. The most well known of such statements is from the Midrash—the collection of exegesis of Torah taught by Rabbinical Sages of the post-temple era—in Bamidbar Rabbah 13:15, which explains that there are "seventy faces to Torah". This perplexing statement is generally understood to mean that the nature of the Torah's truth is multifaceted. Similarly, the Babylonian Talmud states regarding a legal debate that "these and these are the words of the living Lord"; in other words, both opinions are valid. Because no single hashkafa is believed to have a monopoly on the truth, great amount of philosophical flexibility is provided to Jewish thinkers, which results in different—sometimes even contradictory—hashkafas.