Or you could look at the Code of Hammurabi, Buddhism, Taoism, Hinduism, Confucianism and a host of other codes, religions and philosophies that go back as far or pre-date Homer that quite clearly lay out a strict moral and ethical code of conduct. Or you could simply look to the Jewish canon which pre-dates Christ by a year or two at least.
I am using Homer as a “window into the mind”, not a set of precepts, a description, not a prescription.
Hinduism mutated a great deal. I don’t think you will find an ethics as such in the classics. They are very close to Homer. They are stories with Gods in them, not really teachings.
Buddhism did generate a universal ethics, but it made no impression on Mediterranean civilization (unless you want to credit it with an influence on Jesus, which requires fundamentally irreligious assumptions).
And ditto the Tao. None of these pre-date Homer.
Hammurabi’s code, ancient as it is, expresses what amount to tribal customs, that are also strictly functional. Codes of conduct are universal; Islam itself really amounts to a comprehensive code of conduct. Rome had similar laws; that did not lead them to a religious concept of compassion. Laws can exist without an underlying ethic.