Don't be a pessimist. Don’t you realize that all that happens or can happen is for the best?—Your optimism will be a necessary consequence of your faith. (The Way, 378)
In the midst of the limitations that accompany our present life, in which sin is still present in us to some extent at least, we Christians perceive with a particular clearness all the wealth of our divine filiation, when we realize that we are fully free because we are doing our Father’s work, when our joy becomes constant because no one can take our hope away.
It is then that we can admire at the same time all the great and beautiful things of this earth, can appreciate the richness and goodness of creation, and can love with all the strength and purity for which the human heart was made. It is then that sorrow for sin does not degenerate into a bitter gesture of despair or pride, because sorrow and knowledge of human weakness lead us to identify ourselves again with Christ’s work of redemption and feel more deeply our solidarity with other men.
It is then, finally, that we Christians experience in our own life the sure strength of the Holy Spirit, in such a way that our own failures do not drag us down. Rather they are an invitation to begin again, and to continue being faithful witnesses of Christ in all the moments of our life — in spite of our own personal weaknesses, which, in such a case, are normally no more than small failings that hardly perturb the soul. And even if they were grave sins, the sacrament of penance, received with true sorrow, enables us to recover our peace with God and to become again a good witness of his mercy.
Such is the brief summary, which can barely be expressed in human language, of the richness of our faith and of our christian life, if we let ourselves be guided by the Holy Spirit. (Christ is passing by, 138)