Maina received a BA in sociology and religious studies from Egerton University in Njoro, Kenya, then an MDiv from Nairobi's Evangelical Graduate School of Theology.
[1] In this capacity, he spoke to the New Zealand Church Missionary Society in 2006 and became aware of the challenges of work in a secular environment compared to the more religious culture of Kenya.
[1] He has also called on the church to serve as "God's agent for social transformation" in an environment where "[i]n New Zealand, we look to government and community organisations to fix challenges around mental health and well-being.
"[1] At the time of his election, shortly after the General Synod of the Anglican Church in Aotearoa, New Zealand and Polynesia had voted to allow blessings of same-sex unions, Maina had not stated his position.
"[2] The synod of Diocese of Nelson's stated policy since 2004 has been that its ministers are prohibited from participating in or leading any service marriage (or a rite similar to it) for a same-sex couple.
"[4] In September 2020, Maina joined a coalition of other Christian leaders calling on voters to vote no in the ultimately successful 2020 New Zealand euthanasia referendum.