Why did the Nazis and Hitler hate the Jews so much, and why did they have so much support in their anti-Semitism among ordinary Germans? That could take a while. Please do keep in mind that descriptions like "intellectually consistent" do not apply to Nazis, and that anti-Semitism, like any form of racism, cannot easily or cleanly be explained away.
New Synagogue Berlin The church, to begin with, has a history of antagonism regarding Jews. Christian clergy were preaching about modern Jews’ personal responsibility for the death of Christ even late in the 19th century--only in 1962 did the Catholic Church formally renounce that teaching, although no major Catholic leader had openly maintained that medieval attitude in modern times. Arguably the most influential German of all time was Martin Luther, a notorious anti-Semite. He once wrote that Germany should get rid of all the Jews, but not before taking “all their gold, jewels, and furs”; furthermore, he proposed for the Jews “that their synagogues and schools be set on fire, that their houses be broken up and destroyed," and that they "live under a roof or stable like the gypsies, in misery and captivity as they incessantly lament and complain to God about us.”
Lutheranism is the main religion of Berlin and most of northern and eastern Germany. In the 8th century a pope had forbidden usury among Christians; thus, if a Christian needed to borrow some money, he usually had to go to a Jew. Jews became the first bankers and financiers of Europe and were often blamed for financial loss. Later, when Christians were allowed to lend and borrow money from each other, they discovered that Jews were better at it, having had 1000 years experience.
For centuries, the professions available to Jews were limited. In many areas of Europe, they could neither own land nor work for the state. That led them into commerce, sciences, and intellectual pursuits. Thus, they became the some of the best-educated people in Europe. These smart, wealthy people became easy targets (due in part to their traditional dress) during hard times. After the end of WWI, several communist societies sprang up in parts of Germany. A few were led by Jews, and they became associated with the left wing. There were many prominent conservative Jews active at the time--several voted for the Nazis!--but most people ignored that.
There is no shortage of literature out there on German anti-Semitism; for example, those interested should look into the debate between scholars Goldhagen and Browning. You can also just go on a tour and talk with us about it.
Tours: because sometimes books make you sleepy.