This song is about man's desire to kill and destroy. Sabbath got the idea from war stories they heard when they did a show at an American Air Force base during a tour of Europe. They wrote the song when they were in a grim deserted place in Zurich where they were playing for a small sum of money to an even smaller audience.

The band wanted to use this as the title of the album, but the record company thought it was too controversial and made them use "Paranoid," another song on the album, instead.

This is one of many Black Sabbath songs that is often misinterpreted as evil. The song speaks out against the horrors of war.

The song starts with the lyric, "Generals gathered in their masses. Just like witches at black masses." Bassist and lyricist Geezer Butler was asked during a 2013 interview with Spin magazine why he used "masses" twice rather than coming up with a different word. "I just couldn't think of anything else to rhyme with it," he admitted. "And a lot of the old Victorian poets used to do stuff like that - rhyming the same word together. It didn't really bother me. It wasn't a lesson in poetry or anything."

The song was inspired by the Vietnam War. Geezer Butler recalled to Mojo in 2017: "Britain was on the verge of being brought into it, there was protests in the street, all kinds of anti -Vietnam things going on. War is the real Satanism. Politicians are the real Satanists. That's what I was trying to say."

Lyrics

Generals gathered in their masses

Just like witches at black masses

Evil minds that plot destruction

Sorcerers of death's construction

In the fields the bodies burning

As the war machine keeps turning

Death and hatred to mankind

Poisoning their brainwashed minds

Oh lord yeah!

Politicians hide themselves away

They only started the war

Why should they go out to fight?

They leave that role to the poor

Time will tell on their power minds

Making war just for fun

Treating people just like pawns in chess

Wait 'til their judgement day comes

Yeah!

Now in darkness world stops turning

Ashes where the bodies burning

No more war pigs at the power

Hand of God has struck the hour

Day of judgement, God is calling

On their knees the war pig's crawling

Begging mercy for their sins

Satan laughing spreads his wings

oh lord yeah!