‘Desire nothing except to be pleasing to him and to do his most holy will’ [CRE I 28]. This simple formula, inspired by the relationship between Christ crucified and his Father, and lived ever more intensely in the most radical way by Catherine, provides the key to an integrated reading of her spirituality, of which it is the heart. But how does it actually take shape in practice? Will it not don the emaciated face of renunciation, gloomy earnestness, human frustration, all-enveloping pain, self-denial and deprivation? The reality is in fact quite different. There is not a single letter in which Catherine does not invite people to be ‘cheerful’ [cf. CRF VII. 3 163-167], This certainly does not mean a superficial, silly cheerfulness which is only skin-deep and unpredictable in its durability. What Catherine encourages is a cheerfulness which does not exclude the heights and the depths of the various states of spirit people find themselves in as their circumstances vary, whether internally or externally, but which remains constant even in times of pain and tribulation. It is a cheerfulness which is rooted in its depths in the very mystery of God and whose intensity flows from faith, hope and the love with which it abandons itself to God’s plan in the specific life of each individual.