In an open letter sent to bishops before their meeting later this month, synod members call for "greater clarity and consistency" in the Church's approach to the LGBT community.
The bishops are meeting to discuss the next steps after the completion of the two-year "shared conversations", a process of meetings around the dioceses and at synod where church members tried to move towards some form of consensus on the divisive issue of sexuality.
Letter organisers include Jayne Ozanne, a gay member of the House of Laity, and the Dean of St Paul's Dr David Ison, and has been signed by synod members from 37 of the Church's 42 dioceses.
Conservatives fear that there will soon be a shift towards acceptance in Church liturgy of some form of same-sex blessing.
Ozanne said: "The response to the letter has been overwhelming, it definitely seems that the tide is now finally turning. From conversations I have had, many synod members were deeply challenged and moved by the discussions in July, and it seems that many now are keen for the Church to take active steps towards ensuring it is welcoming and inclusive of all."
Canon Giles Goddard, chair of the human sexuality group in Synod and the other lead co-ordinator of the letter, said that the breadth of support was important.
"The broad consensus across the church traditions is extremely encouraging," he said. "We hope it will help the C of E to find ways to heal the deep level of pain felt by many of us within the LGBTI community, by becoming genuinely welcoming and affirming."
Dr Ison said: "I believe that there's a growing consciousness across the Church that our response to lay and ordained LGBTI Christians cannot stay as it is. We need far greater honesty and transparency with one another, and to ensure that all LGBTI people are welcomed and affirmed by a Church called to share the redeeming love of Christ with all."
The 127 signatories include 68 members of the House of Clergy, including three deans and eight archdeacons and 59 members of the House of Laity.