A heathen approached the sage rabbi Hillel some 2000 years ago and expressed an interest in converting the Judaism. But since he was very busy, he would consider it only if the rabbi could teach everything that should be known about the religion while the student stood on one foot. Rabbi Hillel directed the man to stand on one foot. Said the rabbi, "What is hateful to you, do not do to your neighbor. That is the whole of the Torah; the rest is commentary." (Attrib.)
You will, of course, find this same thought at the heart of Christianity, Buddhism and Islam. If the various adherents of these religions would simply follow this one admonition, the world would become the paradise we say we all want.
Love your neighbor and yourself.