Notwithstanding that, because of the fallibility of humans, subjective matters of conduct arise. For example: because of your hardness of heart Moses allowed divorce, but from the beginning it was not so; David was an adulterer which was punishable by death, but repented and was forgiven; mercy triumphs over judgement. As Jesus said: be perfect, as your heavenly father is perfect. Unfortunately, we’ve all already failed.

No scripture is a matter of one’s own private interpretation, but many matters beyond that are, because we complicate matters for ourselves by our imperfection. A lot of the stuff in Paul’s letters he wrote to help resolve such matters.