An official blessing would formalize what has long been an unofficial practice at some dioceses across the country.

Armed with a new $400,000 grant and the support of the Episcopal Church, a Berkeley seminary is convening priests from across the country to craft the liturgical rite for same-sex couples to receive religious blessings.

The new rite, which will take years to complete, will most likely consist of a series of original prayers, Bible readings and two essays: one on the theological meaning of same-sex blessings, and one advising priests who administer the new rite.

If approved, the new blessing would be just the third addition to Episcopal liturgy since 1979.

“This is very significant,” said the Rev. Ruth Meyers, chairwoman of the church’s Standing Commission on Liturgy and Music, who is heading the effort. “It does acknowledge a fuller participation of gays and lesbians in the life of the church.”

The Episcopal Church approved the development of “theological and liturgical resources” for the blessing of same-sex relationships at its 2009 convention, citing “changing circumstances in the United States and other nations.”

It then partnered with the Berkeley seminary, Church Divinity School of the Pacific, which last month received a grant from the Arcus Foundation, a gay rights organization in Kalamazoo, Mich., to coordinate the effort.

Most of the grant money will finance travel and accommodations for a series of meetings to garner contributions from all 110 Episcopal dioceses, most in the United States.

An official blessing would formalize what has long been an unofficial practice at some dioceses across the country. Unofficial blessings have taken place in Bay Area churches since at least the 1980s.

But not all Episcopalians support adding the blessing.

“Doing this will cause great fracturing and great pain,” said the Rev. Canon Kendall Harmon of the Diocese of South Carolina. “It represents a willful American embrace of something that the Anglican Communion has said is out of bounds.”

Ms. Meyers has appointed four priests to draw up the new rite. They represent the progressive side of a schism in the worldwide Anglican Communion, which is fracturing over gender issues.

The Rev. Jay Emerson Johnson, a theologian from the Center for Lesbian and Gay Studies in Ministry at the Pacific School of Religion in Berkeley, will draft the theological essay. The Rev. Canon Susan Russell, who has performed same-sex blessings at a Pasadena church for decades, and the Rev. Canon Thaddeus A. Bennett, a priest in Vermont, where same-sex marriage is legal, will write the essay on pastoral care. And the Rev. Patrick Malloy, a liturgical scholar at General Theological Seminary in New York City, will lead the drafting of new prayers and select biblical readings.

“We’re taking this as an opportunity to offer these resources to the whole church,” Mr. Johnson said, “not just for the sake of gay and lesbian couples but as an opportunity for everybody to reflect theologically on what it means to be in a committed relationship.”