Love is the connection between the manifested world and the Truth. 

Love is the only doorway through which  one may pass between the spiritual and physical world.

When all religious teaching emphasize Love, the objective may have been to ensure we will be the best in our responsibilities and reach our destiny; Love being in the middle of the Truth and the world we manifest. 

Dhi Thesis:

From Love branches sprout higher to bloom the reality in this physical realm, and the roots go deeper to the Truth from which all manifestations are nourished.