This good and gifted man often preached in Philadelphia; not only at stated seasons, on the first and fifth day of the week, but at evening meetings also, where the Spirit is said to have descended upon him and his hearers in such copious measure that they were reminded of the gathering of the apostles on the day of Pentecost.  Isaac was at an impressible age, and on those occasions his thirsty soul drank eagerly from the fountain of living water.  He never forgot those refreshing meetings.  To the end of his days, whenever anything reminded him of William Savery, he would utter a warm eulogium on his deep spirituality, his tender benevolence, his cheerful, genial temper, and the simple dignity of his deportment.

Isaac was about twenty-two years old, when he was received as a member of the Society of Friends.  It was probably the pleasantest period of his existence.  Love and religion, the two deepest and brightest experiences of human life, met together, and flowed into his earnest soul in one full stream.  He felt perfectly satisfied that he had found the one true religion.  The plain mode of worship suited the simplicity of his character, while the principles inculcated were peculiarly well calculated to curb the violence of his temper, and to place his strong will under the restraint of conscience.  Duties toward God and his fellow men stood forth plainly revealed to him in the light that shone so clearly in his awakened soul.  Late in life, he often used to refer to this early religious experience as a sweet season of peace and joy.  He said it seemed as if the very air were fragrant, and the sunlight more glorious than it had ever been before.  The plain Quaker meeting-house in the quiet fields of Woodbury was to him indeed a house of prayer, though its silent worship was often undisturbed by a single uttered word.  Blended with those spiritual experiences was the fair vision of his beloved Sarah, who always attended meeting, serene in her maiden beauty.  The joy of renovated friendship also awaited him there, in that quaint old gathering place of simple worshippers.  When he parted from his dear cousin, Joseph Whitall, they were both young men of good moral characters, but not seriously thoughtful concerning religion.  Years elapsed, and each knew not whither the other was travelling in spiritual experiences.  But one day, when Isaac went to meeting as usual, and was tying his horse in the shed, a young man in the plain costume of the Friends came to tie his horse also.  A glance showed that it was Joseph Whitall, the companion of his boyhood and youth.  For an instant, they stood surprised and silent, looking at each other’s dress; for until then neither of them was aware that the other had become a Quaker.  Tears started to their eyes, and they embraced each other.  They had long and precious interviews afterward, in which they talked over the circumstances that had inclined them to reflect on serious subjects, and the reasons which induced them to consider the Society of Friends as the best existing representative of Christianity.