To one's own personal liking, as in He's very patient with the slower pupils; he's a teacher after my own heart. This idiom appears in the King James Bible of 1611 (I Samuel 13:14). [Late 1500s]
The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.