It also will mean mutual recognition of each church's baptisms and the sharing of communion, said Toms, who was a delegate to her denomination's general synod earlier this month in Columbus, Ohio, where the agreement was approved.
Toms' pastor, the Rev. Jim Williams, hailed the agreement as "a step breaking down the barriers between Christian denominations."
"The churches are keeping their own identities. It is strengthening the ties between our churches," the Rev. David Buchenroth, pastor of Trinity Lutheran Church in Hagerstown, said.
"We're not going to lose our flavor of Presbyterianism," the Rev. Mark Sandell, pastor of St. Andrew Presbyterian Church outside Williamsport, said.
"We all do the same work. We're sort of recognizing we do worship the same savior," Sandell said.
The agreement would affect almost 10 million Protestants - 5.2 million Lutherans, 2.7 million Presbyterians, 1.5 million United Church of Christ members and 400,000 Reformed Church in America members.
"It'll make us more aware of each other" and help celebrate the similarities rather than the differences in the churches, said Bill Price, parish administrator of Trinity Lutheran Church in Hagerstown.
"This is not a new issue. This is a result of talks and discussions that have been going on for a few decades," the Rev. Tom Hartshorn, pastor of Christ Reformed United Church of Christ in Martinsburg, W.Va., noted.
The four denominations "have virtually the same roots" but were divided in the past along national and ethnic lines, Hartshorn said.
"The common heritages have been recognized again," he said.
The main sticking point over the years for the churches has been how to interpret the meaning of the Last Supper and holy communion, Hoffman said.
"We're agreeing to disagree on our understanding of the Lord's Supper but we can preach in each other's pulpit," he said.
While Hoffman called the agreement "long overdue" and "a good trend because Christ prayed that all his people will be one," he also expressed concern about the motivation behind it.
"Is this sort of an attempt to shore up if not a sinking boat one that is tilting a little?" he asked.
Toms said part of the motivation behind the agreement is diminishing membership among the churches, which in turn limits their ability to do good works.
She pointed out that different churches have worked in unison in overseas missions for years.
"The whole society is changing. The church is finally catching up with society," Toms said.
All four denominations must approve the agreement for it to go into effect, Hoffman said.
The Presbyterian Church (U.S.A.) and the Reformed Church in America both approved the agreement in June, he said.
The only denomination that still must vote on it is the Evangelical Lutheran Church of America, which will take up the issue at its biannual assembly in mid-August, Buchenroth said.
Price said the agreement was supported at a regional synod of Lutheran churches in Maryland and Delaware that he attended in June.
One possible stumbling block to passage of the agreement is the United Church of Christ's ordination of homosexuals to the ministry.
But Buchenroth said the Lutheran tradition allows for the ordination of homosexuals as long as they practice a celibate lifestyle.
The Lutheran Church is working on similar ecumenical agreements with both the Episcopal and Roman Catholic churches, he said.
Buchenroth, who is president of the Washington County Council of Churches, predicted that local congregations won't feel much impact from the agreement between the four Protestant denominations.
"I think these churches are already working ecumenically and will continue to do so," he said.
Hartshorn said that in the Martinsburg area there always has been a cooperative spirit among the churches, "so this is not something that's strange. This is a pretty ecumenical area."
Hartshorn is a product of an ecumenical background.
He was ordained in the Methodist Church, did doctoral work at a Presbyterian seminary and serves as pastor of a United Church of Christ congregation, he said.
Hoffman said many members of his congregation come from the Lutheran tradition and had assumed that such an agreement between the churches already existed.
"The leadership is catching up to the laity," he said.
Hoffman practices what he preaches when it comes to ecumenicism. A United Church of Christ minister, he is married to the Rev. Bonnie Hoffman, pastor of Memorial Lutheran Church in Shippensburg, Pa.
Sandell said he expected the agreement to have the greatest impact in areas such as some parts of the west where there aren't many members of these denominations.
They could combine their resources and form "hybrid churches," he said.