Although research and policy suggest science and mathematics teachers should attend to their student's thinking during instruction, our field has inadequately defined what that means in relation to our ultimate goals for the practice. Here I present a theoretical argument that, in making their definitions, researchers should leverage the ways students understand such attention by characterizing teacher attention based on the epistemological messages it sends students about the nature of knowledge and learning in the classroom. Using data collected from high school science and mathematics teachers with a new video‐capture methodology, I present an analysis of variability in epistemological messages of teacher attention to illustrate work could unfold if we as researchers took up the theoretical claims made in this work. In doing so, I endeavor to draw the construct of epistemological messages into our collective conversations about teacher attention, and provide a starting point for our field to begin debating the most productive ways to study and unpack the epistemological messages we value in that teacher attention. I conclude by demonstrating the feasibility of using these messages to distinguish the types of teacher attention our field wants to develop and encourage in teacher education. © 2017 Wiley Periodicals, Inc. J Res Sci Teach 9999:XX–XX, 2017