As a Christian, he viewed his vocation as a commitment, bestowed upon him in baptism, to a lifelong struggle against the "powers and principalities", which he believed systemic evil is sometimes called in the New Testament, or "Power of Death". He proclaimed that being a faithful follower of Jesus means to declare oneself free from all spiritual forces of death and destruction and to submit oneself single-heartedly to the power of life. In contrast to most younger liberal Protestant theologians of his time, Stringfellow insisted on the primacy of the Bible for Christians as they undertook such precarious and inherently dangerous work. This placed him not within the camp of evangelicalism, but that of neo-orthodoxy, particularly the part of that school influenced by the Swiss Reformed theologian Karl Barth, who made a rare compliment to Stringfellow on his only visit to the US. Yet others might classify him as a harbinger of the later liberation theology during the 1970s and 1980s. Although, to be clear, Stringfellow himself was ultimately critical of any self-described political theology that would allow itself to function as a closed ideology. During his lifetime, similar ideas to Stringfellow's could be found in the writings of the French critic Jacques Ellul, with whom he had an ongoing correspondence.