Because these commands seemed burdensome, He proceeds to shew their great use and benefit, saying, “He that findeth his life shall lose it.” As much as to say, Not only do these things that I have inculcated do no harm, but they are of great advantage to a man; and the contrary thereof shall do him great hurt - and this is His manner everywhere. He uses those things which men’s affections are set upon as a means of bringing them to their duty.
Thus: Why are you loath to contemn your life? Because you love it? For that very reason contemn it, and you will do it the highest service.
Reproduced in full. Translation: Oxford 1841 (Newman), public domain (Public domain).