line own 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

line one's own pocket(s)

Fig. to make money for oneself in a greedy or dishonest fashion. They are interested in lining their pockets first and serving the people second. You can't blame them for wanting to line their own pockets.
See also: line, own, pocket