Ttyjukl

I'd always assumed this phrase was iconic because it was a standard part of the intro monologue. Apparently, this is not the case.

In which episodes does it appear? Bonus points for in-context quotations.

From IMDB trivia..

Although the phrase "Submitted for your approval" from Rod Serling's opening narration has come to be closely identified with the show (and is often used by Serling impressionists), it is actually heard in only three episodes: The Twilight Zone: Cavender Is Coming (1962), The Twilight Zone: In Praise of Pip (1963), and The Twilight Zone: A Kind of a Stopwatch (1963).

Excerpt from Cavender is Coming:

Submitted for your approval: The case of one Miss Agnes Grep. Put on earth with two left feet, an overabundance of thumbs, and a propensity for falling down manholes. In a moment, she will be up to her jaw in miracles brought by apprentice angel Harmon Cavender, intent on winning his wings. And though it's a fact that both of them should have stood in bed, they will tempt all the fates by moving into the cold, gray dawn of The Twilight Zone.

Excerpt from In Praise of Pip:

Submitted for your approval, one Max Phillips, a slightly the-worse-for-wear maker of book, whose life has been as drab and undistinguished as a bundle of dirty clothes. And, though it's very late in his day, he has an errant wish that the rest of his life might be sent out to a laundry, to come back shiny and clean, this to be a gift of love to a son named Pip. Mr. Max Phillips, homo sapiens, who is soon to discover that man is not as wise as he thinks - said lesson to be learned in The Twilight Zone.

Excerpt from A Kind of a Stopwatch:

Submitted for your approval or at least your analysis: One Patrick Thomas McNulty, who at age 41 is the biggest bore on earth. He holds a ten-year record for the most meaningless words spewed out during a coffee break. And it's very likely that, as of this moment, he would have gone through life in precisely this manner, a dull, argumentative bigmouth who sets back the art of conversation a thousand years. I say he very likely would have, except for something that will soon happen to him, something that will considerably alter his existence and ours. Now, you think about that now, because this is The Twilight Zone.

According to IMDB, it appears in three episodes:

Although the phrase "Submitted for your approval" from Rod Serling's
opening narration has come to be closely identified with the show (and
is often used by Serling impressionists), it is actually heard in only
three episodes: The Twilight Zone: Cavender Is Coming (1962), The
Twilight Zone: In Praise of Pip (1963), and The Twilight Zone: A Kind
of a Stopwatch (1963).

In context:

• 
  

  Submitted for your approval, the case of one Miss Agnes Grep: put on
  earth with two left feet, an overabundance of thumbs and a propensity
  for falling down manholes.

  
  
  

  —The Twilight Zone: Cavender Is Coming

  
  




• 
  

  Submitted for your approval, one Max Phillips, a slightly
  the-worse-for-wear maker of book whose life has been as drab and
  undistinguished as a bundle of dirty clothes.

  
  
  

  —The Twilight Zone: In Praise of Pip

  
  




• 
  

  Submitted for your approval, or at least your analysis: One Patrick
  Thomas McNulty, who at age 41 is the biggest bore on earth.

  
  
  

  —The Twilight Zone: A Kind of a Stopwatch

  
  

He says something similar in To Serve Man, which predates Cavender Is Coming:

Fantastic! Unbelievable! Respectfully submitted for your perusal: a
Kanamit.

—The Twilight Zone: To Serve Man

And yet everyone who rides Twilight Zone Tower of Terror at the Disney parks hears such an introduction. I suspect that sets it in the public consciousness more firmly since far more people have ridden that ride than have seen all the episodes put together. I can't prove this however since Disney won't release such numbers.