Ken Livingstone said yesterday: "Let's remember when Hitler won his election in 1932, his policy then was that Jews be moved to Israel. He was supporting Zionism – this before he went mad and ended up killing six million Jews."

For those who don't understand why these comments were so offensive, let me explain.

Go and read Mein Kampf. Read the full text of the Nuremberg Laws. Understand what Nazi antisemitism was about.

From the early days of the Nazi programme, way back in 1920, the removal of Jews from German society and state was a key part of Hitler's policies. Here are some extracts from the 1920 National Socialist German Workers' Party programme:

– Only a member of the race can be a citizen. A member of the race can only be one who is of German blood, without consideration of creed. Consequently no Jew can be a member of the race.

– Whoever has no citizenship is to be able to live in Germany only as a guest, and must be under the authority of legislation for foreigners.

– The right to determine matters concerning administration and law belongs only to the citizen. Therefore we demand that every public office, of any sort whatsoever, whether in the Reich, the county or municipality, be filled only by citizens. We combat the corrupting parliamentary economy, office-holding only according to party inclinations without consideration of character or abilities.

Do you see? The policy of the Nazis from 13 years before they took power with the Enabling Act was to remove Jews out of Germany and to deny them citizenship.

When the Brownshirts painted stars of David and swastikas on Jewish shops and intimidated anyone who tried to pass through the doors of such an establishment, it was based on this policy of removing Jews from German society and German land. When the Nazis forbade Jews from practising in the professions, it was the natural extension of this policy of removing Jews from German society and German land.

When the Nazis forbade Jews from marrying or having sexual relations with anyone who was German, it was the natural extension of this policy of removing Jews from German society and German land.

When the Nazis tried to encourage Jews to emigrate, whether to Palestine, America or anywhere else, it was the natural extension of this policy of removing Jews from German society and German land.

When the Nazis rounded up the Polish Jews into ghettos in order to contain them, it was the natural extension of this policy of removing Jews from German society and German land.

When the SD Einsatzgruppen followed up the Wehrmacht's lightning campaign through Russia with mass murders of Jews, it was the natural extension of this policy of removing Jews from German society and German land.

When Heydrich convened the Wannsee Conference in early 1942 to lay out the plans for the Final Solution, it was the natural extension of this policy of removing Jews from German society and German land.

When the ovens of Auschwitz burned up to 10,000 bodies a day, it was the natural extension of this policy of removing Jews from German society and German land, laid down in the NSDAP party programme of 1920.

This programme was already 13 years old when some Nazi officials talked to some Zionists about one possible way of getting rid of Jews from Germany. Do you think those Nazis were Zionists? Do you think they were concerned about the right of Jews to return to the Promised Land? Really? That's what you think, Ken Livingstone?

Hitler didn't "go mad" in the 1940s, he was mad in 1920. While arguably he may not have conceived of the gas chambers 25 years before their existence, his visceral hatred for the Jews and his desire to purge them out of German life, however far that life extended across Europe (and beyond), was the same in 1920 as it was in 1945.

The gas chambers only came about because the mad man of 1920 was the Führer of 1940. He was the same man with the same underlying principles, just in a much more powerful position and therefore able to follow through on the natural path of his beliefs.

Now do you understand why what Ken Livingstone said was so offensive?

Rev Peter Ould is a Church of England priest based in Canterbury. He blogs at www.peter-ould.net.