This art is a calendar of the Omer, the seven weeks between the holidays of Pesach and Shevuot. 

A particular spiritual energy shines on each of these 49 days. These energies correspond to Sefirot in the Tree of Life — the divine map of spiritual consciousness discussed in Kabbalah.

The Sefirot and one of many ways of describing them:

Keter             Divine Source
Chochma      Oneness
Bina              Unconditional Love
Chesed          Loving Kindness
Gevurah       Humility
Tiferet           Balance
Netzach        Eternity
Hod               Thankfulness
Yesod            Unity
Malchut        Central Point in the Heart

The 49 days correspond to the seven Sefirot from Chesed to Malchut within each of the seven Sefirot.

This picture depicts this spiritual progression:

In the upper right is a white rectangle representing the Sefira of Chesed.
In the upper left is a red rectangle representing the Sefira of Gevurah.
In the upper middle is a purple rectangle representing the Sefira of Tiferet.
In the middle right is a rectangle, white with a bit of red, representing the Sefira of Netzach.
In the middle left is a rectangle, red with a bit of white, representing the Sefira of Hod.
In the middle center is an orange rectangle representing the Sefira of Yesod.
The large blue rectangle at the bottom represents the Sefira of Malchut.

Each rectangle contains triangles representing the seven Sefirot within the Sefira. The color coding for these Sefirot is the same as before. The triangle of one Sefira is not visible in each area because it is the same color of the Sefira that encompasses it.

The spiritual light of each day’s Sefira shines that day.  

The final 49th Sefira is Malchut of Malchut. This ascends to the exalted spiritual level of Bina.

Kabbalah describes this progression as a microcosm of our spiritual development to our ultimate state of unconditional love and divine union.