No one is practicing animal sacrifice, which is the only acceptable method of worship in the OT and why followers went to the temple in Jerusalem (the only place where sacrifices to God can be made). (religion.blogs.cnn.com)
I can't think of another holiday where cooking outside is just about the only acceptable method of food prep. (lastingredient.com)
In the field of law, state governments insisted that the only acceptable method of preparing for the bar exam was law school training, and while the states did not prescribe curricula, they exercised control of the quantity and quality of lawyers by requiring the bar exam. (hoagiesgifted.org)