In 1664 Isabel married another active Quaker William Yeamans, who was a merchant in Bristol where the couple set up home. They had two sons and two daughters but William junior and Margaret died in infancy. In 1674 Isabel's husband William died and she made extended visits back to the family home at Swarthmoor with her daughter Rachel and her surviving son, also named William. She began to travel in the ministry, particularly to meetings in the North, leaving her children in the care of their grandmother and aunts, although Rachel died in 1676 at the age of ten.
|Swarthmoor Hall Quaker Tapestry panel|
In 1677 Isabel was chosen to accompany her step-father George Fox, William Penn, George Keith and Robert Barclay, the latter two accompanied by their wives, to preach Quakerism in Holland and Germany. Isabel herself preached to Princess Elizabeth of the Palatinate who admired her 'curious voice and freer way of delivering herself.' In 1678 Isabel travelled in Scotland with Robert Barclay and his wife and for the next dozen years she lived in various places including London and Stockton on Tees, where she was again much involved with women's meetings.
|Lincoln meeting house built by Abraham Morrice|
Isabel was a Quaker pioneer who, although acknowledged as knowledgeable and accomplished by others, defined the true believer as one who had transcended intellectual accomplishments. ‘So look not for [God] in the shadows and forms without the power and substance',she wrote, 'nor be satisfied with the hearing of him by the hearing of the ear, or a notional traditional knowledge.’ She called instead for a gradual spiritual regeneration, an inward response to wisdom’s gentle voice within the soul. ‘Return, return, hearken unto the voice of wisdom; for she uttereth her voice in the streets of the world, and in the midst of the concourse of the people.’