Should Christians Marry Only Christians?

To be a Christian is perhaps the most amazing privilege in the history of mankind. After all, you are called to walk in the footsteps of the master, to sacrifice your will, your time and your energy for one short lifetime. In exchange, you will be given an eternity of godly power and wisdom and be used of God Himself to rehabilitate the world from sin and rule along with our Lord Jesus in righteousness! Such privilege certainly comes with guidelines and requirements - well, what are they? How specifically does God through Jesus guide our relationships?