Psalm 137 has become notorious for the brutality and bloodthirstiness that characterise its last verses. In the face of many past criticisms which rejected the Old Testament as a book of violence, both Christians and Jews need to take texts such as Psalm 137 seriously and interpret them against the social and cultural customs of their time. Before Psalm 137 can be judged against the ethical norms of modern societies, the text must first be understood in its ancient context. The aim of this paper is to show that a better understanding of the socio-cultural background of the Psalm may enhance our understanding of vv. 7-9, as well as of the Psalm as a whole. The hypothesis is that the social values of honour and shame feature so prominently in the Psalm that they form a key to the interpretation of the poem.