He was a devoted and active Quaker with all their convictions of the reality of the unseen world; his name was mentioned time and again in their records as being present at their weddings, meetings, and other undertakings. Sometimes it is spelled Gregg but more frequently Grigg.

Moses' son William A. was called Billy.  He was a faithful member in the Church of the Friends of Westfield Monthly Meeting.  In order for William's sons not to be required to compete with the slave labor of that era, he sent them away to school to be educated.  Billy was a knowledgeable man throughout his era and locale and had the Quaker gentleness of spirit.  He opposed slavery, war, and bloodshed.

During the 1846 election, a time of stress and contention over a slave question, a hired gang of ruffians tried to keep Quakers from voting.  While Billy was adhering to his right to vote at the polls, he ended up being struck over the head with a hickory club at the hands of one of the gang members.  He died a few days later as a martyr to the cause he knew was right.