It is necessary to keep these two truths together, namely, the real possibility of salvation in Christ for all mankind and the necessity of the Church for salvation. Both these truths help us to understand the one mystery of salvation, so that we can come to know God’s mercy and our own responsibility. Salvation, which always remains a gift of the Holy Spirit, requires man’s cooperation, both to save himself and to save others. This is God’s will, and this is why he established the Church and made