Though it might be argued, theoretically, that a Christianity in which [people] know how to picket, but not how to pray, is bound to wither, theorizing is not required, because we can already observe the logic of events. The fact is that emphasis upon the life of outer service, without a corresponding emphasis upon the life of devotion, has already led to obviously damaging results, one of which is calculated arrogance. How different it might be if the angry activists were to heed the words found in The Imitation of Christ, “Be not angry that you cannot make others as you wish them to be, since you cannot make yourself as you wish to be.”
The essence of pietism, by contrast, is the limitation of primary interest to personal salvation. Even today, by the highways, we can see signs paid for by somebody, which urge us to “get right with God.” The evil of this well-intentioned effort lies not in what it says, but in what it so evidently omits. The assumption is that salvation is nothing more than a private transaction between the individual and God and that it can be an accomplished, dated event.
—Elton Trueblood, The New Man for Our Time