Why Did God Create The Devil

Why Did God Create the Devil? Isaiah 14:12-13 Isaiah 14:12 How art thou fallen from heaven, O Lucifer, son of the morning! how art thou cut down to the ground, which didst weaken the nations! 13 For thou hast said in thine heart, I will ascend into heaven, I will exalt my throne above the stars of God: I will sit also upon the mount of the congregation, in the sides of the north: 14 I will ascend above the heights of the clouds; I will be like the most High. 15 Yet thou shalt be brought down to hell, to the sides of the pit. 16 They that see thee shall narrowly look upon thee, and consider thee, saying, Is this the man that made the earth to tremble, that did shake kingdoms;