The universe that we inhabit and our shared perception of it are the results of a common karma. Likewise, the places that we will experience in future rebirths will be the outcome of the karma that we share with the other beings living there. The actions of each of us, human or nonhuman, have contributed to the world in which we live. We all have a common responsibility for our world and are connected with everything in it.
The way of presentation is different according to each religion. In theistic religions like Buddhism, Buddhist values are incorporated. In nontheistic religions, like some types of ancient Indian thought, the law of karma applies. If you do something good, you get a good result. Now, what we need is a way to educate nonbelievers. These nonbelievers may be critical of all religions, but they should be decent at heart.
All major religious traditions carry basically the same message, that is love, compassion and forgiveness the important thing is they should be part of our daily lives.