In addition to the intellectual faculty, the will also brings out a moral faculty — a faculty to endure hardship, to bear suffering, and to remain steadfast in its effort to attain the ideal. This faculty is faith. Faith is not a passive faculty for mere belief. On the contrary, faith is an active power of the will. Faith, as St. Paul tells us, is the substance of things hoped for, the evidence of things not seen. A veil of darkness usually enshrouds us, obscuring our vision, and overwhelming us with fear of the untried and the future. But faith lifts up that veil of darkness, showing us the bright future in the making. By this we are assured of the realization of the things hoped for. Faith enables us to remove mountains of difficulties, and encourages us to persist in our struggle for a better world, despite universal opposition and disappointment. Faith enables us to identify ourselves with our ideal to such extent as to seem to us a present living reality. One that has faith cannot anymore doubt the successful outcome of the struggle for the ideal.--
The Philosophy of Marx, 9.145