by Reb Gutman Locks @ Mystical Paths
Everything in creation has a unique design and function. Nothing has been left to chance. We do not believe that creation is a haphazard affair. We believe that the entire creation, down to the smallest atom, has been planned with great care, with each object having its own nature and purpose for a good reason.
Therefore, the strongest muscle in the human body must have been made that way because of its unique and most strenuous job. Without even knowing which muscle this is, we can understand that we must use it correctly, or the body would be in serious trouble. Obviously, the strongest muscle must have the heaviest work. So, we have to take care that it serves us well--that we use it for good and not (G-d forbid) for harm.
As it turns out, the strongest muscle in the human body, in proportion to its size, is the tongue. The tongue has two main functions. It helps us to eat properly, and it helps us to speak properly. Judging by the results of these two functions, indeed it seems that they are the two most difficult jobs that we have.
Guard your tongue.[i] Be careful how you use your tongue. It can make life very good for you, or it can make it a living hell.