Rashi on Exodus
והיה — This expresses an action continually going on (“and it used to be”),
Siftei Chakhamim
To go to the tent. Rashi is answering the question: Why is it written, “Whenever Moshe went out to the tent”? It should say: “Whenever Moshe entered the tent.” Rashi answers that “went out” refers to Moshe’s exit from the Israelite camp, not Moshe’s tent.
Chizkuni
והיה כצאת משה, “it would be that whenever Moses came out, etc.;” this describes Moses leaving the camp of the Israelites in order to return to his private residence (tent).'