lieutenant is unclear whether he obtained a degree from the University of Oxford, but he is thought to have incorporated at the University of Cambridge (Trinity Hall) in 1741, obtaining Bachelor of Laws and Doctor of Laws degrees in 1742 and 1751 respectively.
After ordination, he became vicar of Llannor with Deneio (near Pwllheli, Gwynedd) in 1723, becoming canon of Bangor Cathedral in 1742 and Chancellor of the cathedral in 1743. In 1745, he was additionally appointed rector of Llantrisant, Anglesey. Whilst his date of death is unknown, his successor was installed "because of the death of J. Owen" on 8 November 1755.
On one action, he prosecuted a priest who had allowed a circulating school to function in his parish.
The case took three years to resolve and, whilst the priest was acquitted, he still had to leave his farm. One contemporary of Owen, the priest John Lewis, said that Owen was "famous for a troublesome litigious temper" and thought it strange that the Bishop of Bangor would want to appoint him Chancellor.