throw in (one's) hand
To give up on some endeavor; to quit or abandon something. An allusion to card games, especially poker. I've been working on this book for over a year, and I'm getting nowhere with it. I think I'm ready to throw in my hand. You'll never find a fulfilling, long-term relationship if you throw in your hand as soon as you have a big fight.
throw in one's hand
Give up, abandon, as in I'm through trying to assemble it; I'm throwing in my hand. This expression comes from card games such as poker, where it is used to retire from the game. Its figurative use dates from the 1920s.