The quote also underlines pretty much what Marx point was. Not “weapons are holy”, but the working class needs weapons, if you want to take it away from the working class you have to use violence to stop the oppressor. In the case of the civil war the revolutionary parties for all practical purposes were the executive body of the working class in party form. Which means that if you are part of the party it is fine to have weapons.

The only argument here would be how the transition of revolutionary parties to body of the working class goes. Vulgar marxist argued, it comes from here: communism is the real existing movement, and so on and so on.

With other words since obviously the civil war which ended up with a soviet republic did change the present conditions those that achieved it were precisely the communist movement. Which if we go with Lenin, who played part in the revolution as we know, were organized in the communist and revolutionary parties of the time. So 100% coherent in theoretical foundation and practical application.