Heaven Is Not The Goal
While Jesus Christ, Immanuel of Nazareth taught unconditional Love, Buddha, Gautama Siddhartha taught Compassion. They are essences of Light, just like a prism disperses different colors. Different masters taught the same spiritual essence but distinctively to the time, the area and the culture. Some saw Light as blue, some saw it as yellow color. They are all Light and different aspects of it. The differences in color represent the differences in religion. There is absolutely no need to argue which color is right or wrong.
In Buddhism, there are six paths in the astral world where the souls transmigrate to. From the bottom to the top layer, there are worlds of Hell, Famine (Starvation), Animals, Human Beings, Militants (Asura) and Heaven. These 6 worlds are in the astral dimension, and Buddhism teaches that Heaven is not the ultimate goal.
Heaven is the highest realm in the astral world, but souls can only go down to the other world from there.
