Why are Holy Orders and Matrimony called sacraments of service?

Both Matrimony and Holy Orders are sacraments of vocation, that is they pertain to a specific path in life a person chooses. These two sacraments, when received, thus give the special graces God has designated and seen as valuable to aid the soul in its chosen vocation. These sacraments are therefore at the service of the individuals who receive them as well as at the service of the Church and society, for the sanctification of any individual aids others in both the Church and in the world.