'Mastery' in the Bible

for we know that the Messiah, who was raised from the dead, will never die again; death no longer has mastery over him.

For sin will not have mastery over you, because you are not under Law but under grace.

And every man that striveth for the mastery is temperate in all things. Now they do it to obtain a corruptible crown; but we an incorruptible.