Father Piotr Semenenko (1814–1886), a Polish Resurrectionist, is the co-founder of a Polish school of spirituality. His conception of the spiritual life is marked by optimism. This comes to the fore in the sermons in the present volume and is illustrated especially by those in which the author speaks about the peace of Christ and God’s love for man. This optimism is based on the Resurrection and flows from the faith in God’s love, which results in the presence of Christ in the Christian and leads him to union with the Risen Christ.