A living lingam - the masculine principle is the spirit, working on the feminine principle

"In many Indian temples, you see the lingam, the symbol of Shiva,
represented – a raised stem on a horizontal base. Those who
give commentaries on the symbol often stop at the raised stem,
which represents the phallus, the generative organ, the masculine
principle. In fact, you should also take into account the
horizontal base, which represents the feminine principle. The
masculine principle is the spirit, working on the feminine
principle, matter. The whole of creation is simply the result of
these two principles working together. And so they should not be
thought of as separate in spiritual practice either.

In India you still come across men and women with a red dot
painted between their eyebrows. That is where the ajna chakra,
the centre of clairvoyance, of spiritual vision, is situated. But
if you concentrate on this chakra, which is receptive, feminine,
you should also concentrate on the sahasrara chakra, situated at
the top of the skull, which is emissive, masculine. When the two
principles are brought together, they become a living lingam. "

Omraam Mikhaël Aïvanhov