Pope Francis' Apostolic Exhoration Rejoice and be Glad--Gaudete et Exsultate involves the call to holiness in the modern world, a topic that has been at the heart of the pontificate of Francis since the beginning. At its outset, Francis makes clear that this magisterial text does not seek "to be a treatise on holiness" but to "re-propose the call to holiness in a practical way for our own time, with all its risks, challenges and opportunities". The pontiff launches a plain, essential message, indicating that what counts, what is the essence of Christian life is to "seek and find God in all things. "It means letting Christ work in our actions. That His thoughts may be our thoughts, His feelings our feelings, His choices our choices. This is holiness, doing as Christ did is Christian holiness." And in this sense he hopes that his "pages will prove helpful by enabling the whole Church to devote herself anew to promoting the desire for holiness". This universal call to holiness is a key teaching from the Second Vatican Council.