How did the devil become?

Answer 1

Some have equated the verses in Ezekiel 28 and Isaiah 14 as being references to the fall of the 'covering cherub' that the Latin Vulgate called Lucifer or morning star:

Ezekiel 28:14-16New International Version (NIV)

14 You were anointed as a guardian cherub,

for so I ordained you.

You were on the holy mount of God;

you walked among the fiery stones.

15 You were blameless in your ways

from the day you were created

till wickedness was found in you.

16 Through your widespread trade

you were filled with violence,

and you sinned.

So I drove you in disgrace from the mount of God,

and I expelled you, guardian cherub,

from among the fiery stones.

Answer 2

Devil is one of the fallen angel from Heaven, as he was not ready to accept God and his supremacy. He is a fallen angel from heaven, who previals in the world interfering in the lives of people who are close to God. As Devil , Satan dont want to accept God or worship him.