This book is an inquiry into the nature of the Deity in view of human relationships. Does the Christian doctrine of Trinity or Islam's doctrine of Tawhidic (monadic) Allah more adequately account for the existence of human relationships and their inescapability? This question is analyzed by comparing the Tawhidic nature of Allah with the Trinitarian nature of God in order to evaluate and clarify which doctrine is the best explanation for human relationships. Thus, this is an abductive argument, inferring from the evidence to the best explanation. By first reflecting on how humanity exists in terms of oneness, distinctness, and relatedness, the doctrine of Tawhidic Allah is investigated to observe how well it grounds these aspects of human relationships. Then, the same is done concerning the Trinity's ability to ground these. The conclusion compares and contrasts the Trinity and Allah to explain which one better accounts for human relationships. Following this conclusion, there are a number of ramifications that are discussed.