Too much lighting. World would not load. How to get back in game to fix???

In one of my worlds I used too much lighting by using command blocks and I put no delay in the ticks so it went super fast. I also did many command blocks of the same thing so I glitched out and I can't get in the game to break the command blocks to stop it. When I try to get in the game it glitches at the loading page and logs me out of Minecraft. What should I do to get back in the world?