In his book Theology of Hope, Jurgen Moltmann comments on the relationship of promise to history: "[God] promises a new world of all-embracing life, of righteousness and truth, and with this promise he constantly calls this world in question -- not because to the eye of hope it is as nothing, but because to the eye of hope it is not yet what it has the prospect of being." When Jesus, the righteous Branch from David, is born of Mary, God fills full (fulfills) history with the prospect of what humanity is destined for, namely reconciled relationship with God.