Responsive teaching-or teaching that builds from the "seeds of science" in student thinking-is depicted in STEM education literature as both important and challenging. U.S. science education reform has been calling for teachers to enact instruction that attends to and takes up the substance of students' STEM ideas; however, responsive teaching represents a substantial shift from the current state of affairs in most U.S. classrooms, where content is often presented authoritatively as facts, definitions, and algorithms, with little consideration of student thinking. Drawing on language from literature about sense-making, this paper identifies some of the "vexation points" that novice science teachers face as they consider implementing responsive teaching practices in science-that is, what doesn't make sense, to teachers, about this instructional approach. In particular, we show that novice teachers express moral concerns about responsive teaching; themes in their written reflections suggest that they perceive responsive teaching to put truth, success, and faith at risk. We argue that though these concerns originally seem distinct from the institutional constraints to responsive teaching posed by the literature, teachers' concerns about truth, success, This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.