I'm not sure why people get religious about this. The far more interesting approach is to try to use reason along side other current laws to determine the answer to two questions - what defines a human life, and when is it acceptable to take one? For example, trying to compare things like medical support for preterm babies to medical support of coma patients to investigate the logic behind viable fetuses vs various life support methods, etc.
I didn't say anything; I'm not the person you were replying to. But I will say that I suspect your arguments that God has the authority over a document people wrote is, again, unlikely to find an audience among those who don't think He exists.
By what divine authority do you say we need not concern ourselves with even the possibility of a divine authority?