An ancient Israelite walks into the Tabernacle carrying a fancy, comfortable wooden chair. He walks up to the High Priest, who looks completely exhausted from standing all day.
"Your Holiness," the man says, "I see you standing there hour after hour. I brought you a gift so you can finally sit down and rest your feet!"
The High Priest gasps, takes a step back, and says, "Are you crazy?! Take that away! There are no chairs in the Tabernacle. If I sit down on the job, it’s a total taber-nackle!"
The man apologizes and says, "Wow, I'm sorry. I just wanted to help. You look so stressed out. What's bothering you anyway?"
The High Priest sighs and points out to the pasture. "See that red cow out there? I’ve been staring at it for six hours with a magnifying glass. If it grows just two white hairs, the whole purification system is ruined! I am totally stressed!"
The man says, "Well, look on the bright side. Once you burn the cow, mix the ashes into the water, and sprinkle it on the people, everyone who was unclean will finally be 100% clean!"
The High Priest throws his hands up in the air and yells:
"Yeah, but do you know what the worst part is? The moment I make them clean, the magic water turns me unclean! So I’ll be completely dirty, I still won't be allowed to sit down, and I'll have to wash my clothes before I can even go home to complain about it!"