"The difference being is that we now have the NEW Testament which means we are no longer under the same penalty for sin as delineated in the Old Testament."
Does your Bible include the Old Testament? If so, then I rest my case. Not all Muslim countries exact the death penalty for adultery, either. Neither does Israel, even though they rely on the Old Testament totally. But, those laws are still in your Bible, right near those Ten Commandments, which you still adopt from the Old Testament.
I realize that those old death penalties don't apply. They don't in most of the Muslim world, either.
Does your Bible include the Old Testament? Yes.
Not all Muslim countries exact the death penalty for adultery, either. True.
Neither does Israel, even though they rely on the Old Testament totally. In fact, they do NOT rely on the OT totally. They've rejected all prophecy pointing to Jesus Christ as the Messiah.
But, those laws are still in your Bible, right near those Ten Commandments, which you still adopt from the Old Testament. Yes. But remember, once Jesus came to fulfill the prophecy of the OT, we (all those throughout the ages since) were no longer bound by the penalty for sin as was exacted throughout the OT.