English, just like other languages, continuously evolves. The changes to the language are slow enough that they are essentially imperceptible during a lifetime, but an English speaker of 500 years ago would not be able to understand the English of 1000 years ago nor today. This document displays how a psalm would have been written 1000 years ago and how drastically it has changed over time.
The language will continue to change and will some day we unrecognizable to us. It might take less time than we think; technology and the need for easy and quick typing seemz 2 hav kicked dez changes into hyperdrive.