If the existence of disagreement over what the Bible teaches means we can’t be sure what the Bible teaches, then the Bible teaches nothing and commands nothing.
The Bible can’t teach us that there is one God, because some believe the OT teaches henotheism.
The Bible can’t teach us that the one God exists in three persons, because some people are modalists.
The Bible can’t teach us anything about sexual ethics, because people disagree on where the Bible draws the lines.
The Bible can’t teach us to serve the poor, because people disagree on who exactly “the poor” are and what our responsibilities to them are.
The Bible can’t teach us to love our enemies, because Jesus may or may not have existed, and may or may not have said that.
The Bible can’t teach us not to be hypocrites, because how do we know those passages weren’t added later as a dig at the Pharisees? (I just made that theory up, which is how we get a lot of smart-sounding ideas about the Bible.)
The Bible can’t teach us that the Gospel is for all sinners, including homosexuals, because there’s this one “church” in Kansas that believes they can’t be saved.
Of course, this is nonsense. Sure, there are lots of topics where there’s legitimate debate over what the Bible means. But there are also lots of topics where the Bible speaks very clearly, and there has been overwhelming consensus for centuries on what it means. When we shrug and say “who’s to say?” we’re not helping anyone. We’re just shooting the Bible in the foot.