God did NOT create satan....satan created satan....God created a perfect being who CHOSE to rebel...thereby becoming "satan" (the accuser of the brethren)...
Thou art the anointed cherub that covereth;
and I have set thee so:
thou wast upon the holy mountain of God;...
...Thou wast perfect in thy ways
from the day that thou wast created,
till iniquity was found in thee.
Ezekiel 28:14,15