"What do we know about the Holy Grail? According to legend, it was carved from an emerald which had fallen from the forehead of Lucifer when he was hurled into the abyss after rebelling against God. Other accounts say it is the cup Jesus used on the evening
of the Last Supper and in which Joseph of Arimathea collected his blood when he was crucified. Whether these accounts are truth or legend, the important thing to understand is that the Holy Grail symbolizes those human beings who have succeeded in drawing the
Holy Spirit to themselves and making it stable within them. Emeralds are green, the colour of Venus, the feminine principle. Blood is ruby red, the colour of Mars, the masculine principle.
So the Holy Grail symbolizes the union of the two principles, the masculine and the feminine, Mars and Venus, but in their highest aspect, where they merge with the Sun (the masculine principle) and the Moon (the feminine principle).
Omraam Mikhaël Aïvanhov