A lot of the reason as to why opposing verses exist in Christianity and I'm only looking at the NT because the OT is a compilation of many incomplete religious texts, is because there's this culture of certainty. Each branch claims the ability to interpret scripture accurately according to their own mindset, prejudice and world view.
If there was open-mindedness and a culture of continuous learning and understanding in Christianity then room for a degree of uncertainty would enable discussion, rather than each having their own dogmatic understanding of scripture.
The next point is that the intended meaning of a subject is scattered in the NT and to ascribe absolute understanding of a subject to a single passage does not produce the best understanding on a subject. It should a process of drawing the best general conclusion whilst leaving room for further understanding.
Lastly, nobody knows the propriety, or accuracy of texts that entered the Bible compilation, nor was it precisely the correct compilation, nor what effect the drift in conceptual understanding of language has had. The Bible started out in oral form and there is certain to a Chinese Whispers effect as well before it was produced in written form. That can be clearly seen in the 4 gospels.
As for God should have been more precise, nothing in the age of the NT comes down to us today as precise. Science, medicine, religion, political and legal structures have to be understand as being relevant to a time and place.
