To Bite Off More Than You Can Chew (Origin)
What Is the Origin of the Saying "To Bite Off More Than You Can Chew"?If someone bites off more than he can chew, it means he has agreed to do more than he can manage.
To bite off more than he can chew dates back to the 1800s in America, where it was common practice to chew tobacco. People would offer others a bite of their tobacco block, and some would greedily take a bite bigger than they would chew. People began to notice this and forewarned others not to bite off more than you can chew.