The meaning of ecumenism is that of  promoting or tending toward worldwide Christian unity or cooperation in the whole inhibited world.[1]

Interfaith ecumenical unity includes the liberal branch of Christianity and other world religions(Islam, Hinduism, Jainism, Roman Catholicism, Judaism, etc.) Ecumenism is now forming the foundation for a one world religious system.

Revelation 17:1-2. Depicts this false religious system symbolize by a woman call the Great Harlot (Rev 17:1). This false religious system is said to influence both the rulers of the earth and its inhabitants(Rev 17:2).

The interfaith ecumenical movement is one of the most clearest signs and has direct bearing indicating that we are nearing the end of the church age. It is clearly a preparation of the fulfillment of religious Babylon (Rev 17:4-6) which will have global influence.

The Babylonian religious system spiritual roots go back to Babylon (Gen 10) and whose future spiritual composition consists of the occultic religious abominations of the world. This false religious system will come into its maturity during the Great tribulation. It represents a rebellious world at war with the God of the Bible. It is a blatant affront to him by violating the first of the ten commandments which state.

Exodus 20:3 (NASB95)
3 “You shall have no other gods before Me.  
"before Me" may mean “in opposition to Me” as well as “in My presence”, [9] either way it strongly implies that God's people are to have "no" association with any type of  foreign god, materialistically, spiritually or other wise. Association with other gods brings with it the danger of godless influence from those who don't now the true and living God.

Is 2:6

6 For You have abandoned Your people, the house of Jacob, Because they are filled with influences from the east , And they are soothsayers like the Philistines, And they strike bargains with the children of foreigners.

There are aggressive efforts to bring all stated Christian (Protestant conservative and liberal, Eastern Orthodox, Anglican, Roman Catholic, Evangelical, Charismatic, and *Pentecostal Churches) groups together. This is not limited to the bringing together of just Christian groups, it includes interfaith ecumenism as well (Muslims, Christians, Buddhists, Hindu's, Janist, etc.). The some of the primary players are the United Nations, National Council of Churches(NCC), World Council of Churches(WCC), Religions For Peace(RFP) and the Roman Catholic Church these are leading the ecumenical interfaith efforts. Their apostate program of global ecumenism is propagated through member organizations and churches, who have taken on the role of the Harlot's daughters.
Click to see membership of NCC  Click to see membership of WCC  Click to see members for RFP

This aggressive effort is fueled by a false interpretation of John 17:11
11 “I am no longer in the world; and yet they themselves are in the world, and I come to You. Holy Father, keep them in Your name, the name which You have given Me, that they may be one even as We are.(NASB95)

No where in this verse or in the  entire prayer of Christ's (John 17:1-26) did he asked the Church or any human agency to answer his prayer. The prayer was directed to the father, this is crystal clear by virtue of the fact that six times Jesus address his prayer to his father (John 17:1,5,11,21,24,25), not to man.

From a Judeo Christian perspective, the uniqueness of the person of Christ, his redemptive work, his second coming and the inerrancy of scripture are no longer seen as being unique.  To accept an interfaith philosophy implies a beliefs that the truth of God can be only found in multiple expressions of faith, i.e. religious pluralism; in other words there is more than one way to God.  Therefore putting all faiths on equal footing. This has undermined the authority of Jesus in the great commission of Matt 28:18-20

In John 14:6 Jesus words of "Jesus said to him, “I am the way, and the truth, and the life; no one comes to the Father but through Me. " have no validity in an ecumenical environment .

The core primary goal of the ecumenist which is demonstrated by their actions is to re-invent Christianity through religious pluralism; as a result historical Christianity as we know it will cease to exist.

The witness of the gospel has been sidelined and replaced with "dialogue" around peace and other "common goals". Biblical truth and commandments has been neutralize by the acceptance and recognition of a perceived equal value of the world's religions. This has resulted in a lost of Christianity's distinctiveness among the world’s religious system.

The interfaith ecumenical philosophy opposes Biblical Christianity in at least the following areas:

Bible’s teaching on true Christian unity
Bible’s warning of false prophets and teachers
Bible’s command to contend for the faith
Bible’s command to separate from error
Bible's command to make disciples
To seek solutions to the world's problems through human effort guided by demonic forces rather than through Christ.

The Bible is clear on what course of action God expects us to take and gives instructions on how believers are to respond during times of apostasy:

Rom 16:17–18 (NASB95) 17 Now I urge you, brethren, keep your eye on those who cause dissensions and hindrances contrary to the teaching which you learned, and turn away from them. 18 For such men are slaves, not of our Lord Christ but of their own appetites; and by their smooth and flattering speech they deceive the hearts of the unsuspecting.

If you are a follower of Christ, I would encourage you to make yourselves aware of your church's associations and affiliations. The web of apostate organizations run deep into the Christian community and many churches, denominations and Para-church organizations are now part of the ecumenical web. The proponents of ecumenism have a desire and drive to bring about world peace through religious unity. This desire is stronger than ever and can be seen in their efforts. Which clearly violate the first commandment:

read more on the efforts to move toward a Global religious system

[1] http://www.merriam-webster.com/dictionary/ecumenical