Bryan was an active member of the Presbyterian Church, and during the late 1750s and early 1760s tried to mediate a conflict that had arisen between two opposing factions of that denomination during the Great Awakening. That experience led to his involvement in local and provincial politics. After Britain's passage of the Stamp Act in 1765, Bryan took an active role in the American opposition, joining other Philadelphia Merchants in signing the Non-Importation Agreement. This likely led to his bankruptcy in 1771.