2043 The fourth precept (‘You shall observe the days of fasting and abstinence 1387 established by the Church’) ensures the times of ascesis and penance which 1438 reparc us for the liturgical feasts and help us acquire mastery over our instincts and freedom of heart.86 The fifth precept (‘You shall help to provide for the needs ofthe Church’) 1351 - eans that the faithful are obliged to assist with the material needs of the hurch, each according to his own ability.’~ I. Moral Life and Missionary Witness 044 The fidelity of the baptized is a primordial condition for the roclamation of the Gospel and for the Church’s mission in the 852, 905 orid. In order that the message of salvation can show the power of s truth and radiance before men, it must be authenticated by the itness of the life of Christians. ‘The witness of a Christian life and ood works done in a supernatural spirit have great power to draw en to the faith and to God.’88 045 Because they arc members of the Body whose Head is 753 hrist,8~ Christians contribute to building up the Church by the nstancy of their convictions and their moral lives. The Church creases, grows and develops through the holiness of her faithful, 828 til ‘we all attain to the unity of the faith and of the knowledge of e Son of God, to mature manhood, to the measure of the stature the fullness of Christ.’90 046 By living with the mind of Christ, Christians hasten the ming of the Reign of God, ‘a kingdom ofjustice, love and peace’.9’ 671, 2819 hey do not, for all that, abandon their earthly tasks; faithful to eir master, they fulfil them with uprightness, patience and love. IN BRIEF 2047 The moral ljfe is a spiritual worship. Christian activity finds its nourishment in the liturgy and the celebration of the sacraments.