Yes. Without a doubt.

At some point in our career we will find ourselves in a situation where the knowledge of a foreign language will be very helpful. And in some cases, necessary.

Knowing a foreign language not only expands your horizons, it expands your business opportunities.  The more proficient you are in a language, the more you will be able to do with it. 

In the beginning you may want to simply have a reading knowledge of a language.

This can be done with the aid of a good dictionary, and a knowledge of the grammar. It's one of the skills that lends itself best to self-study. This skill alone will enable you to do a lot more with your notary commission. 

At some point you will want to be able to converse in a foreign language: have the ability to speak the language, and understand someone who is speaking it.

If you are able to write in the language, you can translate text from one language to another.

Being a multilingual notary gives you more employment opportunities.  There are many businesses that are global, and that can use the services of a multilingual notary.

Having knowledge of a foreign language is a great way to make new friends and bridge cultural gaps.

Capitalize on existing opportunities, and create new opportunities by learning a foreign language.

Good luck.