What concept held the feudal relationship together?

The feudal relationship was primarily held together by the concept of mutual obligation and loyalty. Lords granted land, known as fiefs, to vassals in exchange for military service and protection, creating a hierarchical system of power and responsibility. This bond was often formalized through ceremonies that emphasized loyalty, such as the act of homage, where vassals swore allegiance to their lords. Additionally, the intertwining of social, economic, and political duties reinforced these relationships, ensuring stability within the feudal system.