"Nothing perpetuates ignorance worse than unenlightened enthusiasm," said Major Ian Thomas, one of my major influences in the Christian life. When Christians (or anyone, really) run around talking about things they have no real understanding of, this creates misunderstandings of the truth and perpetuates ignorance, the lack of real knowledge.
C.S. Lewis, another major influence, warned about the dangers of words that are misused, meaning words applied in a way that isn't in agreement with their true definition. Thus, the misuse of the word alters the definition in the public mind. An example of this would be the word, "gay", which once meant light-hearted, carefree, cheerful, happy. But, due to misuse and misapplication, the primary definition has changed in public understanding to mean "homosexual". Whereas the word at one time meant only one idea, now it has been truncated from its original definition and is rarely ever (and maybe, can never be) used in that way. "Gay", in its original sense, has been lost, by and large.
Lewis foresaw the dangers of misusing words and warned that once we begin to use words outside of their true definition, the result would be confusion and a communication breakdown, creating multiple definitions which could be used to fit one's own tastes or group agenda. In other words, there would be no absolute definitions; words would mean what one wanted them to mean. As a result, truth and understanding would become relative and muddied with no clear meaning at all.
I believe this has happened with the word "radical". Most Christians, upon hearing the word, think of ideas like extreme, "on fire", extraordinary, unfettered, maybe even "revolutionary". But the original meaning of the word means something completely different from all of these. Radical means "rooted". It's where we get the word "radish" from. So, to be radical means to be "rooted". Not quite as glorious and exciting as "extreme" or "on fire", is it? But the true meaning of the word teaches us some important truths about living a vital and real Christian life, truths that we need to seriously consider.
Radical means "rooted; i.e., to be like a root". A root is buried in its source of life. "Therefore, as you received Christ Jesus the Lord, so walk in him, rooted and built up in him..." (Col. 2:7). If a root is ever pulled up from the life-source, it dries up - and so does everything that depends upon it.
Another characteristic of a root is that it's stationary. A root doesn't "unplug" itself and go somewhere when it wants. A root is "put" - it's where it's at because someone (really, Someone) wanted it there. Roots that get uprooted too often usually do not thrive. Roots are satisfied with where they stay put.
That being said, the sign of a good, healthy root is that it will produce life and ultimately fruit wherever it's planted. A healthy root will "bloom where it's planted". One of its secrets is this: when things get tough, they don't uproot themselves and go somewhere else. They quietly go deeper into their source of life. When it's dry up top, they reach even deeper; they become even more "rooted" in their surroundings.
A radical Christian is a "rooted" Christian. This doesn't mean they won't be sent out from time to time. But that's the key: roots never move themselves; the gardener moves them - or they won't move at all.
Now that we know what the word "radical" really means and implies...