The fourth Spehirah Chesed is the beginning of manifestation, the externalization of the combined potencies of Kether, Chokmah and Binah. It is the first Sephira below the Abyss, the beginning of the Microprosopus as the realm of actual existance, the first manifestation of the human consciousness as it corresponds to Ruach - the intellectual mind.
Chesed is the central Sephirah in the Pillar of Mercy, situated directley under Chokmah. Emanated from Binah it is the son of those two Supernals, organising and preserving all of the power that was born by Binah from Chokmah's semen. It is the form that Binah had determined for existance and that now becomes actual and real.
Associated with Jupiter (Zeus), Chesed is a benevolent ruler whose name translates as 'kindness', it is the power of growth and expansion, stability and extension, willing to provide structure and stabilty. Kind of nature, it also represents charity and generosity.
In the Tarot Chesed is represented by the Fours and Four is its mystical number. We have seen that Kether is the point, Chokmah the line, Binah the two-dimensional plane, and as noted in the Naples Arrangement the next figure in the order is the three-dimensional solid body. Hence the symbol assigned to Chesed is the pyramid, a tetrahedron which brings together four sides.
See below the Tarot cards corresponding to Chesed - the Fours: