The bible says not to use government currency.
Mark 12:16
"Why are you testing Me? Bring Me a denarius to look at." They brought one. And He said to them, "Whose likeness and inscription is this?" And they said to Him, "Caesar's." And Jesus said to them, "Render to Caesar the things that are Caesar's, and to God the things that are God's."
Modern day:
"Why are you testing Me? Bring Me a dollar to look at." They brought one. And He said to them, "Whose name is this?" And they said to Him, "Federal Reserve's." And Jesus said to them, "Render to the Federal Reserve the things that are the Federal Reserve's, and to God the things that are God's."
Genesis Block
And when money failed in the land of Egypt, and in the land of Canaan, all the Egyptians came unto Joseph, and said, Give us bread: for why should we die in thy presence? for the money faileth.
Genesis 47:15
The old money in Egypt had failed. There was now a new money: grain. It had the characteristic features of money. It was divisible, portable, easily recognized, and had high market value in relation to volume and weight. In normal times, grain lacks this fourth feature. But in a famine, it temporarily gains it. This is why, during famines, grain is money. This is why those who possess it wind up wealthy, assuming they are not killed.
"You can't eat gold." I used to hear that one from people who ridiculed the gold standard. But this is not a good argument against gold. It is an argument in favor of food. Not only can't you eat gold, you can't paper money and plastic credit cards, either. When food is short, money is no longer valuable in comparison to food. Money cannot sustain life. Food can. The forecasts of the Egyptians had been incorrect. They had kept their money rather than buying up food the previous season to store it. Joseph’s forecast had been correct. This put him in charge of Egypt’s future.
But what if the Egyptians had heard about Joseph’s dream and interpretation? What if all of them had believed the story? Their money would have failed the previous year. Had they all gone out to buy up the crop, they would have found that their competitive bids raised the price of grain. This price increase would not have been so radical as it was the following year, when there was a drastic reduction of the grain supply, but it would have been sufficient to turn grain into money.
http://reformed-theology.org/ice/newslet/bet/bet97.08.htmWho own the BTC ?Q. Can I convert one currency in my wallet (e.g. EUR) into another currency (e.g. USD) in another wallet?
A. No, it is not possible to convert EUR to USD directly from one wallet to another as
Mt.Gox is not a currency exchangeQ. What is the exchange rate used?
A. The European Central Bank's daily exchange rate is used.
https://support.mtgox.com/entries/20800336-Multi-Currency-TradingBlame The Banker not Bitcoin.