Readings can add to the solemnity of an occasion, or provide a welcome moment of light relief.
Above all, readings underline the importance of your day by articulating the deep values underlying your momentous decision to marry. Exactly how secular the text can be will depend on the church in question, but perhaps also on the minister. A traditional high Anglican vicar, for instance, might allow some Shakespeare, but draw the line at modern poetry, whereas a 'trendy vicar' might consider a much wider selection of texts. Both, however, would want to ensure that the readings do not undermine the Christian view of marriage, so always make sure your choice is approved by the minister or celebrant. Similarly, in weddings that take place in state-licensed venues, a registrar will need to approve your choice of readings.