"If a demon, why would God make use of a demon?"
His creatures are created for His purpose!
Job 12:13-25
With God is wisdom and might; He hath counsel and understanding.
Behold, he breaketh down, and it cannot be built again; He shutteth up a man, and there can be no opening.
Behold, he withholdeth the waters, and they dry up; Again, he sendeth them out, and they overturn the earth.
With him is strength and wisdom; The deceived and the deceiver are his.
He leadeth counsellors away stripped, And judges maketh he fools.
He looseth the bond of kings, And he bindeth their loins with a girdle.
He leadeth priests away stripped, And overthroweth the mighty.
He removeth the speech of the trusty, And taketh away the understanding of the elders.
He poureth contempt upon princes, And looseth the belt of the strong.
He uncovereth deep things out of darkness, And bringeth out to light the shadow of death.
He increaseth the nations, and he destroyeth them: He enlargeth the nations, and he leadeth them captive.
He taketh away understanding from the chiefs of the people of the earth, And causeth them to wander in a wilderness where there is no way.
They grope in the dark without light; And he maketh them to stagger like a drunken man.
Romans 9:17-21
For the scripture saith unto Pharaoh, For this very purpose did I raise thee up, that I might show in thee my power, and that my name might be published abroad in all the earth. So then he hath mercy on whom he will, and whom he will be hardeneth.
Thou wilt say then unto me, Why doth he still find fault? For who withstandeth his will? Nay but, O man, who art thou that repliest against God? Shall the thing formed say to him that formed it, Why didst thou make me thus? Or hath not the potter a right over the clay, from the same lump to make one part a vessel unto honor, and another unto dishonor?
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God can and does do whatever He pleases, with whoever He pleases, whenever He pleases!
