Or the idea of karma in Indian philosophy. Both Buddhism and Hinduism have the idea that whatever deeds you do in life will lead to consequences, particularly moral consequences. If you give money away in this life, then in the future you may be wealthier and in a positon to help others more. If you are miserly or steal from others, then in the future you will have even less.
Of course, this won't convince anyone who doesn't already believe in karma, but it may be useful to remember that ideas of justice - whether cosmic or man-made - often come down to giving people what they deserve.