Well, I'll tell you. It's purely mercenary. My father offered him a job.
4 seconds sound clip from the It's a Wonderful Life (1946) movie soundboard.
You can hear this line at 00:36:37 in the Blu-ray version of the movie.
Quote context
[...]
- Well, how do you do? Congratulations. How do you do? What am I doing? Congratulations!
- Doggone it, Harry, you... They're married!
- Why don't you tell somebody?
- Come on, Mrs. Bailey, I can't wait to see everybody's reaction.
- You're really married? What's a pretty girl like you doing marrying this two-headed brother of mine?
- Well, I'll tell you. It's purely mercenary. My father offered him a job.
- Well, Harry's cup runneth over.
- George, about that job. Ruth spoke out of turn. I never said I'd take it.
[...]