Tantra or tantraism is an ancient Indian tradition of beliefs and meditation and ritual practices that seeks to channel the divine energy of the macrocosm or godhead into the human microcosm. Polarities Merging into Unity - lovely classical symbols and Deity images to invoke the balancing of male & female energies.
"Tantra is the natural way to God, the normal way to God. The object is to become so completely instinctual, so mindless, that we merge with ultimate nature – that the woman disappears and becomes a door for the ultimate, the man disappears and becomes a door for the ultimate."
Osho, This Very Body the Buddah, Vol.1 Talk #8