On theism, why do humans have moral duties even if there are objective moral values?

[Pnerd]

I'm not asking about worshipping; I'm asking why theists believe they have a moral duty towards other humans (I agree that was not made clear in my question). And secondly, the last part of my question was "other than for a selfish interest in going to heaven or avoiding hell". Your answer seems to be about god's reward and punishment as a motivation for theists to do good. By the way, why is worshipping god = good according to a theist (other than divine reward/punishment)?

You need to realize that man (humans) made god(s), therefore any requirement for worship (which is group manipulation) and corresponding following of commands (control) were also requirements conceived by man (humans). At one time in history (even current history) this was used as a way to control and manipulates groups/societies. The man made concept of heaven was the carrot, hell the stick, repentance a loop hole that let a person get back the carrot.

So it's actually the humans that conceived of the 'morals' that they wanted implemented in their society, again, for control and manipulation. One could argue that it, for the most part, was for the societies benefit (but not always, especially on an individual level). As an inducement to follow the morals they invented/created a god(s) that would provide/enforce the ultimate reward and/or punishment.

I do realize that. That's the secular non-theistic view. That wasn't my question at all. I asked why humans have moral duties towards others from a theistic perspective (apart from the reward/punishment thing). I wanted to know why a theist might think that they have moral duties and obligations. One obvious reason is the hope of receiving a reward or avoiding punishment. I wondered if there are any other reasons and what they might be.

Also, don't you think most humans are self serving? It is the same for most living creatures. Their 'moral duty' typically stops when the 'self' is threatened.

My point was not to pass a value judgement on self-interest. I was asking whether there are reasons other than self-interest for believing (from a theistic perspective) that humans have moral duties and obligations towards others.
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