The Manhattan Declaration: A Call of Christian Conscience is a manifesto issued by evangelical, Catholic, and Orthodox Christian leaders to affirm support for the pro-life movement, traditional marriage (vs., for example, same-sex marriage), and one's right of freedom of religion (in particular, condoning civil disobedience against laws contradicting those understandings of life and marriage). It was drafted on October 20, 2009 and released November 20, 2009, having been signed by more than 150 American religious leaders.
The drafting committee includes evangelical leader Charles Colson, Princeton University professor Robert P. George, and Beeson Divinity School dean Timothy George. 
The signatures of those known for softer sentiments toward ecumenism and leanings toward outward shows of unity such as Ravi Zacharias, Ron Sider, J. I. Packer, Leith Anderson, Ken Boa, James Dobson, Jerry Jenkins, Tim Keller, Joseph Stowell, Kay Arthur, Jonathan Falwell, Wayne Grudem, Josh McDowell and anyone connected with Christianity Today. A bit more surprising are Mark Bailey, Randy Alcorn, Bryan Chapell, Joni Eareckson Tada, Michael Easley, Michael Youssef, and in particular Albert Mohler, President of Southern Baptist Theological Seminary. Joining this roster of evangelicals are numerous Roman Catholic and Eastern Orthodox priests and bishops. Vocal opponents include R. C. Sproul, John MacArthur, Michael Horton and Alistair Begg.  
Those who opposed the document say that:
It must first of all be recognized that Satan is more than willing to give ground on moral and secondary matters if by doing so he can compromise or cripple the gospel message or its proclamation. I believe The Manhattan Declaration does this in a number of ways:
It confuses the gospel. Although no clear definition for the gospel is found within the document, we are repeatedly assured that the signatories all believe and preach the same gospel message. This is reinforced by the clear indication throughout that evangelicals, Roman Catholics and Eastern Orthodox are all “Christians” and thus members of Christ’s body. This is a subtle but serious dilution of the understanding of the Christian faith.
It confuses the Christian mandate. While we all lament the loss of certain freedoms and the moral decay that is increasingly evident in our culture we should remind ourselves of our calling. What our Savior commissioned us to do is clearly stated in Matthew 28:19-20 and Acts 1:8. We are called to make disciples of all nations, teaching them what the Lord has taught us and baptizing them in the name of the Triune God. The church is not called to change society by legislative action, lobbyist activity, or moral declarations.Read more about the opposing view of this ecumenical document.