Renewal coven, like all Path covens, is secular.
A student is required to, by the end of the Seeker cycle, have a belief system that they practise earnestly and honestly. The Path does not require you to abandon your faith or convert.
If you practise a faith that embraces the use of magic we do require that no magic be practised unsupervised once the Seeker oath is taken; this is something that is discussed in depth during the Questioner cycle in order to help students define the difference between a religious ritual and a magical one from the perspective of this requirement.