thats simple question to answer, "it is written" dont be unevenly yoked, what fellowship has light with darkness, even old testament made it clear to marry your own kind, not to marry foreigners. Now im sure many people will be saying now so does that mean i only marry my own ethic race, no im not saying that however im saying that we are the foreigners here in this land passing thru, not to entangle ourselves with this world, we are a strange people, without a vision the people persih, if the vision isnt the Cross at Calvary then what is, only true mercy lovekindness encouragement can be found there. Corinthians makes mention of the unbeleiver and the beleiver, but to me that speaks of if one or the other accepts Christ as their saviour and has converted with a humble and contrite heart then be assured that His Spirit will win the other over by ones willingness to follow Him for He will answer the desires of your heart. There are many marriages that have failed or the believer in the marriage is never really content and at unease in thier Spirit by not following Gods plan for life to start with.