When was Satan Created?

The devil was certainly created before the creation of the world. Job 38:4-7 [4] Where wast thou when I laid the foundations of the earth? declare, if thou hast understanding. [5] Who hath laid the measures thereof, if thou knowest? or who hath stretched the line upon it? [6] Whereupon are the foundations thereof fastened? or who laid the corner stone thereof; [7] When the morning stars sang together, and all the sons of God shouted for joy?
See All... tells us that when the foundation of the earth was laid, "the morning stars sang together, and all the sons of God shouted for joy." These were the heavenly beings and the devil had certainly already been created.

Also, the devil was “a murderer from the beginning” (John 8:44Ye are of your father the devil, and the lusts of your father ye will do. He was a murderer from the beginning, and abode not in the truth, because there is no truth in him. When he speaketh a lie, he speaketh of his own: for he is a liar, and the father of it.
See All...) and he “sinneth from the beginning” (1John 3:8He that committeth sin is of the devil; for the devil sinneth from the beginning. For this purpose the Son of God was manifested, that he might destroy the works of the devil.
See All...). To what beginning does this refer? It must refer to the beginning of the six-day creation. Nothing else makes sense.

However, if there is no gap and the devil was created on the first day of the six days of creation, he must have been created as a sinner and a murderer—since he was these things from the beginning. But this is impossible for two reasons.

• First, this interpretation would make God the author of sin.
• Second, the Bible clearly states that the devil was perfect from his creation and that iniquity was not found in him until a later date (see Ezekiel 28:15Thou wast perfect in thy ways from the day that thou wast created, till iniquity was found in thee.
  See All...).

He was perfect at the time of his own creation, but was a murderer and sinner at the time of the beginning or creation as we experience it. Therefore, the devil had to fall in sin somewhere between the time of his creation and the beginning of the world as found in the first chapter of Genesis. Only the gap provides a time for this. There is no other option.