The Amish Speak More Than One Language

Technically speaking, the Amish are trilingual. They speak English, which is the language they use to communicate with the outside world. They also speak a variant of German only spoken by this community, and they use this language to read the Bible. They also speak Pennsylvania Dutch while communicating with people within their communities.

The reason they speak German and Dutch is because the Amish are immigrants from Germany, and they have never stopped speaking these languages despite moving continents.