We set out to investigate preservice teachers' beliefs about sources of teaching knowledge and their motivation to learn from practice and theory in teacher education in a longitudinal study (n = 96, at the beginning of the study). Participants placed more trust in experiential knowledge sources compared with formalized sources and participants' beliefs about sources of teaching knowledge generally predicted their motivation to learn from different sources. Quantitative results were further supported and elaborated by qualitative interview data that suggested development of preservice teachers' beliefs about sources of teaching knowledge and their understanding of the relation between theoretical and practical knowledge over time. The findings extend existing literature by providing a window on how (preservice) teachers may articulate their views about sources of teaching knowledge and relations between theory and practice, with expected consequences for teaching practice. Implications for teacher educators' practice are also discussed.