Hi there,
Remember that the whole module is about a comparative study of texts and if you're doing it right your going to have to realise that when you look closely at the content of your chosen texts its clear as daylight that there are similar ideas explored by both. The major difference would be though that they were written in different periods and contexts.
So to form a thesis you would have to address that despite the differences in context the two books you explore share some similarity and that by observing this it is clear that the past can have an influence on the future. (think about the definition of cautionary tale).
I'm sure there are plenty of ways you could attack the question and form a thesis but remember, answer the rubric and you should be fine. It also depends on what texts you do and what is the relationship between past and present in those books. To put it simply, your thesis should just be a reflection of what is your answer but at the same time exhibit an element of the differences in context between the two texts.
