שרש המצוה ידוע, שהוא כדי ללמד נפשנו לאהב הטוב והתועלת ולהדבק בו, ומתוך כך תדבק בנו הטובה, ונרחיק מכל דבר רע ומכל דבר השחתה, וזהו דרך החסידים ואנשי מעשה אוהבים שלום ושמחים בטוב הבריות ומקרבים אותן לתורה, ולא יאבדו אפילו גרגיר של חרדל בעולם, ויצר עליהם בכל אבדון והשחתה שיראו, ואם יוכלו להציל יצילו כל דבר מהשחית בכל כחם, ולא כן הרשעים אחיהם של מזיקים שמחים בהשחתת עולם, והמה משחיתים את עצמם במדה שאדם מודד בה מודדין לו. כלומר, בה הוא נדבק לעולם, וכענין שכתוב (משלי יז, ה) שמח לאיד לא ינקה רע. והחפץ בטוב ושמח בו נפשו בטוב תלין לעולם זה ידוע ומפרסם.
The root of this commandment is well-known - it is in order to teach our souls to love good and purpose and to cling to it. And through this, good clings to us and we will distance [ourselves] from all bad and destructive things. And this is the way of the pious and people of [proper] action - they love peace and are happy for the good of the creatures and bring them close to Torah, and they do not destroy even a grain of mustard in the world. And they are distressed by all loss and destruction that they see; and if they can prevent it, they will prevent any destruction with all of their strength. But not so are the wicked - the brothers of the destructive spirits. They rejoice in the destruction of the world, and they destroy themselves - [since] in the way that a person measures, so is he measured; which is to say that he clings to it forever, as the matter that is written (Proverbs 17:5), "the one who rejoices in calamity, will not be cleared (of evil)." And the one who desires the good and rejoices in it, 'his soul will dwell in the good' forever. This is known and famous.
Rabbi Samson Raphael Hirsch, 19th cent. Germany, Horeb, #56
"Do not destroy anything" is the first and most general call of God... If you should now raise your hand to play a childish game, to indulge in senseless rage, wishing to destroy that which you should only use, wishing to exterminate that which you should only exploit, if you should regard the beings beneath you as objects without rights, not perceiving God Who created them, and therefore desire that they feel the might of your presumptuous mood, instead of using them only as the means of wise human activity -- then God's call proclaims to you, "Do not destroy anything! Be a mentsh! Only if you use the things around you for wise human purposes, sanctified by the word of My teaching, only then are you a mentsh and have the right over them which I have given you as a human. However, if you destroy, if you ruin, at that moment you are not a human but an animal and have no right to the things around you.