In the post-conciliar teaching of the Church, in view of the challenges faced by religious communities, there are numerous appeals to remain faithful to the founding charism in their life and mission. The question of understanding this charism and its formation has therefore become the subject of deeper theological reflection. The main purpose of this study is to show how the word of God became part of the process of discerning and developing the charism of the founder of the Salvatorians and Salvatorian Sisters, Blessed Francis Mary of the Cross Jordan (1848–1918). A special witness of this path is the Spiritual Diary he had been writing for more than 40 years, which became the main point of reference in the reflection undertaken. Realizing the chosen goal, the place of the Bible in the life of Blessed Francis Jordan was first pointed out. Then the special action of the Holy Spirit in the life of this religious founder, which is described as fundamental inspiration, was discussed. The culmination of the considerations undertaken became a reflection on the dynamics with which the word of God, especially the passage John 17:3, illumined the path of discernment and formation of his founding charism.