Luke 22:43–44

"Then an angel appeared to Him from heaven, strengthening Him. And being in agony, He prayed more earnestly. Then His sweat became like great drops of blood falling down to the ground."

"Our Lord, from the night in which he sweated (Lk 22:44), changed the sweat of labour [exerted] on a land that produces thorns and thistles (Gen 2:18) into the sweat that accompanies prayer, so that [man] might sweat in the work of righteousness."