The behavioural minimum for morality include A sense of fairness, Empathy (The ability to understand and share feelings), Pro-social behaviour (Cooperativeness, reciprocity, a desire to reconcile conflict) No sacred scriptures are required, nor religions, nor gods required. That is not to say that Religion is not a significant aspect of human culture (as just about every culture incorporates the sacred as well as the profane, and that it satisfies a number of admittedly beneficial and benign human needs, in contrast to the baneful aspects of religion). Morality Without Religion
Unfortunately not everyone is capable of this without following a set of rules. There are people who don’t do bad things because of fear of punishment, societal or spiritual. When the spiritual threat of punishment is gone and the societal threat of punishment breaks down those people become very dangerous.
If you need the threat of burning in hell for all of eternity to be a good person, then you aren't a good person.
You always need some way to both pass on a sense of morality to the next generation and in some coherent manner that all agree to and is accepted by all. That usually requires that it be codified and taught by some grouping beyond the family and be enforced on those that either due to "developmental" faults or mental abilities are unable to conform with the group norms. While I am the first to admit that religion as a basis has a lot of faults and some versions of the reality taught by certain groups is distasteful and downright dangerous. The track records of societies that removed it from religion and reverted to a written law taught by the education system and enforced by law are not performing well either. I think that until we mature more as a society, the jury is out on any system of morality. The present "me" generation has rejected most of our common values and replaced them with a sense of a self center bias that only they and their views count. Most legal systems and those involved in the operation of the system have in the long run been captured by some group in the society. I have met more honest church leaders than lawyers in my life. The real problem is that in fact no one has ever solved the problem of how a group should coexist. Some systems have been reasonably successful for the majority of the individuals, but so far no one has developed a system that is both fair and totally inclusive. We have not up until this point in our existence been able to come up with an all knowing team of fair minded moderators to act as judges in the game of life. In fact much of the conflict in our past has been between the different groups of moderators and their desire to have the ultimate power over how a society operators. Christian, Moslem, Mao, King, any ideology or government in general have killed and enslaved most people thru history in order to maintain or expand their view of morality.
Do you know how many people obey the law because they REALLY don't want to go to jail! Also, lots of folks REALLY don't want to go to HELL! There is an old saying, "I say there ain't no heaven, but I pray there ain't no hell"!
Unfortunately the default setting on most people is not good. I’m not saying its evil either… Most people do what they do out of self interest, true altruism is exceedingly rare.
Humans will instinctively default to the level of behavior that society will allow and will continue that behavioral pattern until corrected. They will emulate their parents or the tribe they wish to be accepted by.