My involvement within each of these denominational settings, both lay and pastoral positions, has assured me that, when it comes to sharing the gospel and the pursuit of evangelism, we are not on the same page.  Evangelical churches often believe the sole obligation of the church is to "win souls" and to seek and save "the lost." Mainline denominations tend to prefer social engagement under the guise of the Franciscan mantra, "share the gospel always, if necessary use words." So, is the church called to verbal declaration or social transformation?
The dichotamy is false.
However, should a Christian long to speak of the gospel in the public sphere or extend to their neighbor an invitation to follow Jesus, Mainliners shout, "Evangelical," as if it were a deragatory term. Evangelism is assumed as an insensitive infringement within a politically correct culture- an offense to the religious beliefs of others. I confess: altar calls make me uneasy, too.
Still more, should a Christian feel called to advocate for the poor, homeless, hungry, and oppressed, even to seek justice and peace in a world obsessed with war and bent towards the rich, Evangelicals shout, "liberal. leftist. secular sell-out." I confess: sometimes subverting the empire becomes more my cause than sharing the gospel.
Again, it seems that Evangelicals and Mainliners are not on the same page.
Yet, when attendance drops, budgets turn red, and pews (or comfy chairs) are abandoned, we begin to contemplate the vitality of the once condemned praxis of our denominational neighbors. All of a sudden a holistic gospel for the whole world, in word and deed, is deemed appropriate and faithful.
This is evident in the Evangelical world, as more and more once-fundamental congregations and institutions have begun to ring the social justice and advocacy bell. The same holds true for Mainliners, whose dying establishments and instutions on life-support, now quest to reclaim evangelism as a spiritual discipline and ecclesial obligation. I am indeed grateful for these awakenings, convinced that hearts and minds of congregations can change. Yet I wonder, are there hidden agendas behind Evangelical and Mainline pendulum swings and missional paradigm shifts? Are evangelism and advocacy efforts merely utilized as tools for new church growth strategy and budget bolstering? Do we open our lips and underscore social change out of fear, anxiety, and the threat of institutional death or do we do so because we are convinced this is the Way of the kingdom?
A recent Christian Century article, "New Clergy, New Churches," referenced Missional Theologian, Darrel Guder, and his increasing evangelistic concern:
While I value the contributions of Guder and consider his work deeply influential to my understanding of church witness, to suggest a need to "talk about evangelism" in order to prevent ecclesial death seems contrary to the gospel and the bulk of Christian theology. Even more, to mention that we need to incorporate evangelism in seminary curriculums and train pastors for preservation of their ordaining institutions seems inconsistent with missional theology in particular and Christian theology in general.  That is to say, neither evangelism nor advocacy, proclamation nor social concern, should generate from the need to save our church or tradition. Instead, we incarnate these disciplines as a called and sent people, directed by the love and grace of God, who live into a realized future. 
"Guder said the church's decline has sparked interest in evangelism within mainline denominations. 'If we don't talk about evangelism, our churches are really going to die. I don't think that infuses the curriculum of any mainline seminary. But I think it's beginning to.'"
Karl Barth says it best:
This is a hard word. We do not want our faith communities to die. We need the revenue in our congregations in order to further function and operate as a ministry movement. Yet, we must refrain from allowing anxiety and fear, which can stem from both the threat of decline and the color red, to serve as sole cause and ulterior motive for evangelism and advocacy. If we fail to do so, what we have to offer our neighbors, brothers, and sisters, is no longer real love that complements the love of God, but rather manipulative mission pursued out of lust, angst, and fear. If that be the case, we may decline and fade anyway.
"Christian love as the complement of love to God is real neighbourly and brotherly love to the extent that it is exercised without any ulterior thought or question, being shown freely and purely to the neighbour as neighbour and the brother as a brother, being shown only because in his Christian and also in his non-Christian form he is a member of the people of which Jesus Christ is the King...Where love exists in both dimensions without any ulterior motive, where it is grounded in itself and does not try to be anything but a necessary response to the love of God, it is that 'fulfilling of the law' of which we read in Mk 12:29 and Rom 13:10" (Church Dogmatics IV, p. 107, italics mine).
Nonethless, God has used stranger things throughout history than the decline in membership rolls to cause a people to repent and change directions, to open mouths and confront consciences (Numbers 22). That said, if the threat of decline leads to the spread of the gospel and a concern for the poor and oppressed, so be it. Maybe even thanks be to God.
 This is not in and of itself a bad thing. The plural nature of the church and the diverse expressions of Christian witness can actually be a gift of the Spirit, who cannot be contained by any one tradition, context, theology, missional praxis, rigid teacher, or trendy preacher. Instead, God reveals God's self in the plurality of truth as embodied by God's people, despite the many hiccups and flaws evident in and through each of them...to include this unfinished blogger.
 I realize that this is neither the thrust of the article, nor is it Guder's primary evangelistic motivation; however, this statement threw me for a loop when I read it. Even more, it is an underpinning for much of what goes on in church strategy and planning today. We are often motivated by numbers and bottom lines versus a longing to conform ourselves more and more to the image of Christ and inaugurate God's future into the present.
 Another related Barth statement, "[Christians] do not merely live under the promise, which could be said of all men. They live in and with and by the promise. They seize it. They apprehend it. They conform themselves to it. And therefore in their present life they live as those who belong to the future" (Church Dogmatics IV, p. 120). That seems like a much more healthy and faithful rationale for evangelism and advocacy.
 Oscar Romero's words have echoed in my mind for many years, "Don't measure yourselves by your numbers. Measure yourselves by the sincerity of heart with which you follow the truth and light of our divine Redeemer" (The Violence of Love, 38)