| work done for the sake of one's own enjoyment or of benefit to others rather than for material rewards: He coached amateur baseball teams as a labor of love. |
labor of love
Work done for one's satisfaction rather than monetary reward. For example, The research took three years but it was a labor of love. This expression appears twice in the New Testament (Hebrews 6:10, Thessalonians 1:3), referring to those who do God's work as a labor of love. [c. 1600]