In this opening letter, Aldhelm addresses King Geruntius, whom he regards with deep respect and fraternal charity. He acknowledges the king's authority over the western kingdom and his role as a scrutator of hearts and witness of truth. Aldhelm, serving as an abbot, humbly conveys his wishes for health and well-being to the king and to all priests of God in Domnonia, emphasizing a spirit of community and shared faith.