Needless use of jargon. A lot of it is denomination - or group - specific. For example, a certain parachurch ministry I am familiar with would invariably slip into Evangelical jargon. For example, "Jesus in your heart." Another example would be the buzzwords used within my former denomination ("New Testament Principles" - i.e., those church structure practices we like to emphasize).
And do you agree with the biblical position of Christ's death on the cross as penal substitutionary atonement (He paid the price for our sins)?
With a key caveat, absolutely. The Penal Substitutionary system is a model designed to explain a "spiritual" or Biblical phenomena. Take a Chemistry example. Remember the "solar-system" models of the atom? They were good for explaining atoms to little kids - but they were an explanation, not the reality. In college, you learn about orbitals, and get these odd shapes around which electrons tend to be located - but, while these orbitals were a more precise model, it still could not be confused for the reality.
The penal substitutionary model of the atonement - that Christ , in a legal sense, paid the price for our sins is a model which the Bible uses to explain the means by which God makes sinners righteous because of the death of His Son. That is, still, a model used for illustration. The reality - that Christ died in the place of sinners - is far more inexpressible than a simple illustration.
(This approach, incidentally, is plagarized from C.S. Lewis. Sharp guy, that C.S. Lewis.)
Does the emergent church that you know of agree with it?
Absolutely.
All emergent-types that I have read and encountered promote re-defining all historical biblical doctrines, including: salvation, sin, atonement, repentance, holiness, separation, and etc
As I have said before, I have limited exposure to the Emergent movement, and from what I've seen, I can understand some of where the Emergent church is coming from. There's a lot of people who had bad experiences with the Church who benefit from an Emergent-style message. The only Emergent church with which I am at all familiar has made it their mission to reach out to people who have had bad experiences with other churches, and try to bring them back into historic Christianity.
Does the emergent church that you are familiar with promote contemplative prayer and other Catholic, mystical practices?
These sound like buzzwords. I will say this - if you are going to slam something as "Catholic," I am not biting. That's not necessarily a bad thing. As regards mysticism, well, I don't think the church is. One of my friends involved in the group is decidedly more mystical than I - the source of many intriguing discussions.
Why is it your former denomination?
What specifically were those church structure practices we like to emphasize?
And where are you attending/serving on a regular basis, now, as a member?
"It is a model..."
No, it is not. It is a biblical reality.
Isaiah 53:5 - "But he was pierced for our transgressions, he was crushed for our iniquities, the punishment that brought us peace was upon him, and by his wounds we are healed."
2 Corinthians 5:21 - "God made him who had no sin to be sin for us, that in him we might become the righteousness of God."
I Peter 2:24 - "He himself bore our sins in his body on the tree, so that we might die to sins and live for righteousness; by his wounds you have been healed.
Many emergents decry substitutionary atonement as cosmic child abuse and a vile doctrine.
And you never answered the question...What are the legitimate concerns (as you stated) of the emergent folks?
It can't be that they don't use jargon because what they teach, and the language they use, is a hundred times more confusing!
I will leave the slamming of all things Catholic up to the reformers...They did a great job and many paid with a great price (many with their lives).
It is main stream emergent to incorporate unbiblical, mystical practices (contemplative prayer, yoga, centering prayer, breath prayer, labyrinth, spiritual guides, transcendental meditation, and etc.) Mysticism, and these practices, are decidedly anti-biblical. Christians experience, and gain knowledge of, God through His Word not through the experiences of true self via a divine center in some eastern religious practice.
All emergent churches define themselves as "missional". It's just the mission, with their message, that they are on that is the problem (a mission of rebellion).