Love Potion #9?
A man named Irving goes to seek counsel from his Rabbi.
"Rabbi, something terrible is happening and I have to talk to you about it."
"What's wrong?" Asked the Rabbi
Irving replied, "I think my wife is poisoning me."
The Rabbi, very surprised by this, asks, "How can that be?"
Irving pleads, "I'm telling you Rabbi, I'm certain she's poisoning me! What should I do?"
The Rabbi then offers, "Tell you what. Let me talk to her, I'll see what I can find out and I'll let you know."
A week later the Rabbi calls Irving and says, "Well, I have spoken to your wife - I spoke to her on the phone for three hours. You want my advice?"
Irving anxiously responds, "Yes."
"Take the poison," says the Rabbi.