The General Convention of The Episcopal Church in 1997 reaffirmed that each and every member of The Episcopal Church is a missionary. This has been the case at least since 1835 when "Domestic and Foreign Missionary Society" became a part of the legal name of the church.
Resolution A205 World Mission Sunday
ADOPTED by 1997 General Convention
Resolved, That the last Sunday of Epiphany of each year be designated World Mission Sunday, and be it further
Resolved, That educational opportunities be provided at every level of the church in preparation for the celebration of World Mission Sunday to increase awareness of and participation in world mission; and be it further
Resolved, That mission networks such as Companion Dioceses, parish linkages, voluntary missionary societies, and the Anglican and Global Relations Office of the Episcopal Church Center be urged to develop and promote resources for the celebration of World Mission Sunday.
Explanation
Every member of the Episcopal Church is a member of a missionary society, The Domestic and Foreign Missionary Society. Whether we understand the imperative of mission from the perspective of the Great Commission or the Great Commandment, or a combination of both, we are united in the one call to God's mission in the world. As God sent Jesus into the world, we too, are sent into the world. This resolution calls upon the church to hold up and celebrate our shared commitment and call to mission on a specific and common Sunday each year. It challenges congregations, dioceses, and provinces to learn about and become more fully engage in God's global mission.