However, the church will still not marry same-sex couples. Former Dean of St Albans, the Very Reverend Jeffrey John, supported the change but described it as a "halfway house" that did not go far enough.
The Evangelical Fellowship opposed the move, saying it did not uphold the "standard of Christian marriage between one man and one woman".
But the church said it was a step on the way towards repentance of a history which has "demonised and persecuted gay and lesbian people".Individual clergy will be able to opt out of offering blessings to same-sex couples and some conservatives said the change would cause a split. The bill authorising a service of blessing was passed by all three orders of the church's governing body at a meeting in Newport.
The bishops passed it unanimously, the clergy passed it by 28 to 12, with two abstentions, and the laity passed it by 49 to 10, with one abstention. The change is significant because a blessing, in theological terms, signifies God's approval. Bishop of St Asaph, Gregory Cameron, who introduced the bill, said he felt "no sense of triumph", but added that "the Church in Wales has done the right thing under God for the LGBTQIA+ community".
Ruth Eleri James (see photo left with her partner Hannah) has both a personal and professional interest in the vote. As a woman in a same-sex relationship, she said she supported giving recognition to relationships like hers as a means of showing their validity in the wider community.
She is also a trainee priest with the Church in Wales. Although unable to vote on the proposed change because of her junior status, she said she would back the bill all the way if she were able to, as has her partner Hannah, a lay member of the governing body. She said: "It's so important to us because it will reflect the real love and welcome that we have personally experienced in our local churches, who we know long to be able to offer something to couples who are in same-sex relationships.
"But it's also important because this is a message to LGBTQ folk in society at large to say their relationships are loved and blessed by God, and that's a message that hasn't been given, certainly in my lifetime, and I long to be able to share that with people."
Ruth said she saw the contradiction expressed by other people in the LGBT community that the church would still not offer full marriage even as it blesses legal unions formed outside of its walls.
"Hannah and I feel strongly that God is asking us to be married one day and we will continue to hope and work and pray for the day when we can have what we call the sacrament of marriage in a church," she added.
"I do see the difficulty in not being able to have that and I do see the point of people who say this doesn't go far enough. But I think a step towards justice is a step in the right direction."