Morality is not some transcendent universal word or concept independent of human thought or language. Nor, was such a term invented by the authors of the Bible. The term 'morality' is no more or less a human conceptual term, derived by human beings in the past at some point, and is also associated with 'well being.'
From my estimation, the words 'morality' and 'well being' appear directly synonymous with one another. If one of the main objectives is the 'golden rule', (whether you adhere to Jesus or Confucius), then one could make a sound case for such.
To answer your question, one could instead argue that without a supreme moral judge or arbiter, there exists no bases or standard, as we are instead comparing one human opinion to the next. Yes, most might agree. However, what if the dictator of a nation disagrees? By what standard might one appeal to in 'proving' this dictator is mistaken (rhetorical)?
However, if such a scenario does exist, it is also plausible that we instead have no morality, but instead 'moral dictates', as humans are to follow the commands passed by the 'moral arbiter.' or 'authority'. Which basically means we are following orders with no evaluation of our own.
In conclusion, to answer the OPer's question, let's start by directly comparing the term 'morality' to 'well being', as it becomes difficult to call something 'good' or 'bad' without recognizing that the two terms are synonymous with one another.