Teleporting long distances will have you ending up several blocks down, and in some cases even out of the world resulting in death.

To recreate, teleport to 1000 ~ 1000 or an area of the world that has not been loaded yet.

After teleporting, you will end up underground suffocating (or if your lucky, in a cave) or even in the void or a lava pool

 EDIT : Glitch does not work when teleporting into an area with water (eg, ocean, a lake, etc)