Prose

Somebody asked, "If money is the root of all evil, was it money that caused the devil to be evil? If it was, how was it possible when there weren't yet any form of money in existence back then?"

Actually, it's not the money itself that is the root of all kinds of evil. Because whether we like it or not, money is a necessity. Money is simply a means of trade.

1 Timothy 6:10 says, "For the love of money is the root of all evil: which while some coveted after, they have erred from the faith, and pierced themselves through with many sorrows" (KJV). So it's not actually the money that is the root of all kinds of evil - it's the "love of money" that is. "The love of money" in Greek is (a) "philargyria" which can also be translated as "covetousness", which in turn means (b) "feeling, expressing, or characterized by a strong or immoderate desire for the possessions of another:" We can infer from these definitions that it was actually love of possessing that is the true root of all evil.

Now going back to the Greek word "philargyria", its root word is the Greek (c) "philarguros" which is a fusion of Greek words "philos" (love or fondness) and "arguros" (silver). Silver (Gk. "arguros), in the ancient times, was prized as a standard measure of worth, value, or gain (which is the reason why bullions made out of it was used as money back then). So when we talk about "the love of money" in its Biblical context, we also talk about the love or fondness (Gk. "philos") for personal gain.

From these definitions, we learn that love for personal gain is what causes evil. For instance, the devil wanted to become equal in order with God (Isaiah 14:12-14). So to him, ordinal equality with God was a personal gain. Another instance was the story of the Fall of Man. Back in the Garden of Eden, Eve was deceived by the devil that eating the fruit of the knowledge between good and evil will make her a deity (Genesis 3:5). We can assume that she relayed the same words to Adam. So to Adam and Eve, deification (becoming a god) was a personal gain.

By reading the 4 preceding verses of our topical verse here (i.e., 1 Timothy 6:6-9), we will learn that the very root of this fondness of personal gain is discontentment. The reason why the devil desired to be equal in order with God was his discontentment with his position as "the anointed cherub that covers" (Ezekiel 28:14). In the same way, the reason why Adam and Eve desired become gods was their discontentment with their superiority over other earthly creatures (Genesis 1:26).

But given that the devil and the man were given such high honors, why were they discontented? The answer is simple: they failed to appreciate the goodness of what God has blessed them with. And they failed to appreciate their blessings because of their lack of gratitude. They thought that what God gave them wasn't good enough for them. As the American philosopher Francis Schaeffer puts it (d), "The beginning of man's rebellion against God was, and is, the lack of a thankful heart." And if, in the same way, we fail to appreciate God's goodness towards us, we might as well fall on the same old trap.
 
So in summary, ingratitude is the root of discontentment, which is the root of covetousness (which is the same as the love of money), which is the root of all kinds of evil.
 
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Sources:
(a) http://biblehub.com/greek/5365.htm
(b) http://www.thefreedictionary.com/covetousness
(c) http://biblehub.com/greek/5366.htm 
(d) True Spirituality by Francis Schaeffer, Chapter 10 - The Law and the Law of Love, p. 10