Life in Christ 495 IN BRIEF 2047 The moral life is a spiritual worship. Christian activity finds its nourishment in the liturgy and the celebration of the sacraments. 2048 The precepts of the Church concern the moral and Chris tian life united with the liturgy and nourished by it. 2049 The Magisterium of the Pastors of the Church in moral matters is ordinarily exercised in catechesis and preaching, on the basis of the Decalogue which states the principles of moral life valid for every man. 2050 The Roman Pontiff and the bishops, as authentic teach ers, preach to the People of God the faith which is to be believed and applied in moral life. It is also incum bent on them to pronounce on moral questions that fall within the natural law and reason. 2051 The infallibility of the Magisterium of the Pastors ex tends to all the elements of doctrine, including moral doctrine, without which the saving truths of the faith cannot be preserved, expounded, or observed.