Lucifer was in Eden as a nice guy, probably for quite a while. Ezekiel tells us that Satan got proud; he was lifted up. He said, "I am a god." He was lifted up because of his wisdom, because of his riches, because of his beauty, and because of his power. The four things that still corrupt people today: wisdom, riches, beauty, and power.
Creation seminars (2003-2005) - The Garden of Eden