Mosese Vitolio Tui was born on 9 November 1961 in Apia, Samoa. He attended the Salesian novitiate in Lysterfield, Australia, entering in 1986, and made his first religious profession in 1987. Perpetually professed on 8 December 1992, he was ordained a priest on 3 December 1994 in Alafua, Samoa, becoming the first Salesian Samoan.
Throughout his service in various communities of the Salesians of Don Bosco in the Province of AUL, he has held several significant positions:
- Administrator and Teacher in Alafua, near Samoa (1995)
- Local Councillor in Oakleigh, Victoria, Australia (1996)
- Local Councillor, Principal, and Community Vicar in Alafua (1997-2006)
- Rector and Novice Master in Suva, Fiji (2006-2009)
- Rector, School Principal, Parish Priest, and Community Administrator in Salelologa, Samoa (2009-2017)
- Rector and Parish Priest of St. Paul in Massey, Diocese of Auckland, New Zealand (2018-2022)
- Warden in Salelologa (2022-2023)
- From 2023, as mentioned, Parish Priest of St. Paul Parish in Massey, New Zealand. For the AUL Province he served as the Provincial Councillor (2009-2015 and from 2022 to date) and as the Superior for the Pacific Delegation (from 2022 to date).