The framing of education and learning in sustainable development has evolved out of global environment and development discussions to shape how knowledge, learning and action are applied in efforts to address complex socio-ecological and sustainability challenges of the times. Such framings have over time contributed not only to the establishment of the importance of education and learning in issues of environment and development--sustainable development--but also to the definition of what forms education and learning should take. Education for Sustainable Development (ESD) has since emerged from such framings in international discussions to pave the way for the formal recognition of the role of education and learning in the global quest for sustainable development. While the ESD discourse has since evolved to become a pragmatic educational ideology and tradition; while many countries and institutions have embraced its ideals in practice, not a lot of attention has been given to the seemingly "instrumentalization" of education in the ESD discourse. This work foregrounds ESD as an emergent discourse to critically explore how education has been framed in the discourse. Through Discourse Analysis and Critical Discourse Analysis, the paper examines the coarseness of words used in creating the ESD discourse across time by paying close attention to texts--specific language use--in key "discourse moments" to understand how linguistic choices, power, and institutional structures have helped to create a role for education in sustainable development and how that has facilitated the formation of the ESD discourse.