The angels on the top of the Ark face each other. In this form, the Divine Presence could be felt in the Tabernacle. A baby has a face of peace and contentment and doesn't deal with fights and wars. According to the Sages, the faces turned away from one another when the Hebrew nation sinned and faced each other when G-d was pleased with His Chosen People. It is known that the Menorah symbolizes wisdom.
Light brings wisdom.
Among all of the vessels of the Tabernacle, the Ark is the heaviest. It was written that the Ark carried itself when Israel crossed the Jordan River and it also carried the people who held the material.