Born in
Scotland, he was named after his father,
William Bailie, a native of
Ayrshire. He was educated at
Glasgow University, but graduated with a
Doctorate of Divinity from
Oxford University. His father had the construction of a
fortified house, completed in 1613, and
enclosed the
demesne by 1629. The estate became known as the Manor of Bailieburrow, which was later known as
Bailieborough. On the death of his father in , Dr Bailie inherited the estate. Little is known about his wife, but it is certain that they had a daughter Jane, who married James Hamilton of Coroneary and had issue. The Hamilton family remained at Bailieborough for another two generations: they included
John Hamilton MP. ==Ecclesiastical career==