Hebrews 12:11

the peaceable fruit of righteousness The original is expressed in the emphatic and oratorical style of the writer, "but afterwards it yieldeth a peaceful fruit to those who have been exercised by it (the fruit) of righteousness." He means that though the sterner aspect of training is never pleasurable for the time it results in righteousness in moral hardihood and serene self-mastery to all who have been trained in these gymnasia (γεγυμνασμένοις). See Romans 5:2-5.