Matthew Cabot is introduced early in Tarnsman Of Gor as Tarl Cabot's father. He had disappeared while Tarl was still an infant and had been missing for more than twenty years when he and Tarl meet again. Before they met again, Tarl found a letter that is apparently over 300 years old, dated "1640" with his father's signature on it.
Matthew is the first person Tarl meets upon regaining consciousness after having stepped into a spacecraft that in the White Mountains of New Hampshire. As he enters the room, Matthew is described similarly to Tarl, tall and red haired. He appears to be in his mid 40s. Matthew explains many things to Tarl though not all the son is wanting to hear. He eludes to Tarl's mother not being the 'only one'.