Chapter 11, “Truthfulness”
Chapter 11 makes comments on Matthew 5:33-37, where Jesus prohibits swearing oaths. This passage and the practice of making oaths has been difficult for the Church to apply. Often in history, “mature” Christians would not make oaths, but others would. Some groups reject all oaths while others reject frivolous ones. Bonhoeffer observes that Jesus made promises before a court of law and Paul often uses oath-like expressions.
Bonhoeffer defines an oath as (Loc. 1903) “an appeal made to God in public . . . invok[ing] the omniscient deity to avenge the truth.” If this is the case, we would have no reason to avoid oaths when we know the truth certainly. Yet swearing an oath may leave open the possibility that the Christian is not truthful when not under oath. Of course, we also do not have exhaustive knowledge or perfect memory of all events, so we are always open to error.
Jesus’ command in Matthew 5:33-37 is finally a claim for truthfulness. Bonhoeffer (Loc. 1941) again makes a distinction between those who genuinely and completely follow Jesus and others, even though the others may in fact believe Jesus. The true disciple, then, is truthful.