ask me no questions, (and) I'll tell you no lies

ask me no questions, (and) I'll tell you no lies

Don't question me on that topic because I will probably lie. I'm not going to tell you what we're planning for your birthday, so ask me no questions, and I'll tell you no lies. A: "We want you to tell us the absolute truth about this." B: "Ask me no questions, I'll tell you no lies."
See also: ask, lie, no, tell
Farlex Dictionary of Idioms.

ask me no questions, I'll tell you no lies

If you want the truth, better not ask directly. Listed in the Oxford Dictionary of Proverbs, this saying recurs throughout 150 years of English literature, from Oliver Goldsmith’s She Stoops to Conquer (1773), in which the lies are “fibs,” to George Bernard Shaw’s Man and Superman (1903).
See also: ask, lie, no, tell
The Dictionary of Clichés by Christine Ammer
See also:
  • FAQ
  • as I was saying
  • IANA
  • a mine of information
  • hot take
  • IANAE
  • (one) could go (on) all day (about something)
  • a vexed question
  • as for
  • as for somebody/something