line your pocket

line (one's) (own) pocket(s)

To make a large amount of money for oneself in a way that is considered greedy or dishonest. The phrase typically implies that one is prioritizing making money above some other, more admirable goal. He doesn't care about creating some digital utopia—he's just trying to line his own pockets. This new contract is going to line our pockets for years.
See also: line
Farlex Dictionary of Idioms.

line your pocket (or pockets)

make money, usually by dishonest means.
See also: line, pocket
Farlex Partner Idioms Dictionary
See also:
  • line (one's) (own) pocket(s)
  • line one’s own pocket
  • line one’s own pockets
  • line one's pockets
  • line own pocket
  • line pockets
  • line your /somebody's pocket
  • line your pockets
  • for (one's) (own) sake
  • for sake
References in periodicals archive
Money can't buy everything and you can't buy an oasis like this to line your pockets.
Do away with the trash; line your pockets with cash.