Context

This line is found in Exodus 5:1, but it also shows up in [deep breath] 7:16; 8:1, 20, and 21; 9:1 and 13; and 10:3 and 4.) 

Moses famously says this line when he and Aaron appear before Pharaoh. As you can see in the full quote, it's actually a quote of a quote: Moses tells Pharaoh that the God of Israel said it—Moses is just the messenger.

The phrase is repeated often enough that it becomes kind of like a protest slogan for Moses and the Hebrews. #letmypeoplego was definitely trending on whatever the ancient Hebrew version of Twitter was.

Where you've heard it

You pretty much can't read this quote without singing it in your head, right? Blame "Go Down, Moses," an iconic African American spiritual that's been sung since at least the 1850s. In the song, Israel (as we're sure you've already guessed) represents African American slaves, while Pharaoh represents the slaves' masters.

Additional Notable References:

• "Go Down, Moses" is referenced all the time in popular culture: From 1986 classic Ferris Bueller's Day Off to The Fresh Prince of Bel Air to the 2010 film Easy A.
• And you thought that other song about letting go was overplayed.
• This line has also spawned other songs, such as this little number from The Prince of Egypt.
• Legendary actor Charlton Heston bellows this line as only he can in Cecil B. DeMille's epic The Ten Commandments. Just let 'em go, Yul Brynner!
• Yvon Chouinard, founder and owner of outdoor gear company Patagonia, titled his autobiography Let My People Go Surfing. Sounds good to us.

Pretentious Factor

If you were to drop this quote at a dinner party, would you get an in-unison "awww" or would everyone roll their eyes and never invite you back? Here it is, on a scale of 1-10.

If the Fresh Prince can use this line, can't we all?