Receiving a letter from somewhere in a dream signifies wisdom and weighty words.
Seeing oneself write and send a letter to a known person, instructing that person toward goodness and virtue, signifies elevation of one's standing, fulfillment of needs, and the path of Truth. Receiving a letter containing glad tidings signifies safety from what one fears and a good outcome. At times, this dream signifies a wife and a child.
Seeing oneself beat the person who brought a letter signifies the dreamer's falling into error and, at times, death.