There's a lot of stuff to think about in Mark 10:35-45, and especially in that last verse. It's a verse that has been appropriated for the development of a theology of atonement, even substitutionary atonement, in a way that doesn't really work with the material Mark has given us here.
The sermon for this scripture explores this challenge to a degree. Much of that atonement talk hinges on how modern users ("modern" here applying to several centuries' worth of interpreters, not just us "modern" American types) apply a definition of "ransom" that doesn't really fit. The "ransom" in Mark's usage doesn't imply anybody getting paid for the release of those held captive, which doesn't fit with the notion that some price had to be "paid" for our release from sin, that price being Jesus's life in such theology. (Really, though, would not Jesus's resurrection somehow equate to a breach of contract in such a theology?)
An awful lot (yes, there are two possible ways to interpret that, and both are valid) of theology has been spilt trying to fit this passage with other bits of scripture, such as some of the "suffering servant" verses from Isaiah, to flesh out this theology of a price to be paid. I'm not sure, though, that it's this bit of interpretation that causes the most damage.
It's possible to be incredibly narrow in defining the word translated "life" in this verse. As noted in the sermon, the word in question (ψυχην, "psuxen") goes far, far beyond any definition of "life" that can be reduced to "not death." The word wants to embrace all the stuff of living, not just a biological definition of being alive. And this is the biggest problem for a lot of theologies out there.
Like John and James in this passage, it's easy to talk tough. When Jesus challenges their seating request, asking if they can really endure all the suffering he's about to endure, they have the cheek to respond "we are able." Were they counting on some kind of divine intervention to head off the very suffering and death Jesus had tried to teach them three times now? Were they just stupid? What is it?
Like many of the January 6 insurrectionists, who are now sounding a lot less brave with prison time looming as a real possibility, one can't help but notice that these two brave-talking disciples have, later in this gospel, bolted and deserted Jesus by the time he is nailed to the cross. Eventually the book of Acts reminds us that James, willing or not, did eventually drink from this cup of suffering; he is noted as the first of the twelve to be martyred (of course Judas died first, but not a martyr's death). John apparently doesn't die such a death, but the tradition that he spent years in exile does suggest suffering did come his way.
Even so, for an awful lot of human beings, giving up being alive is a far easier promise to make than giving one's life, particularly in the way Jesus gave his life, particularly in the way Jesus came to serve and not to be served. Being "manly" or "tough" or a "warrior" has become the default way of being "Christian" for an awful lot of men who claim that name. (Many, but not all, of such men are affiliated with church traditions that can be described with a five-syllable word starting with "e".) If you're willing to twist your brain enough I suppose that can be passed off as a kind of "service," but let's get blunt: there's nothing Christlike about it.
Right there is a word - "Christlike" - that needs to be recovered and put to work a lot more than it typically is in the church of whatever stripe these days. In the current state of society, where the word "Christian" as adjective has been so stretched and distorted as to be nearly useless for anything meaningful, I still say it's worth breaking out "Christlike" in its place and seeing just how much of what we describe as "Christian" really measures up.
Following a Savior who steadfastly refused to rack up power on earth loses its luster real fast for a great many people. Signing up for a fight sounds better. Even better is the promise of being "ransomed" - getting the great "get out of Hell free" card - without having to follow the example of Jesus, to give your whole life, your inner self, your soul, your everything. Talking as if your "salvation" is in the past tense is a lot easier and more fun than talking about your service, your following Jesus, as an ongoing everyday thing.
Resist this.
It might just be that the allure of the "get out of Hell free" card is the biggest problem with the misuse of verses such as this one. Anything that implies that the Christ-following life, or any part of it, is an over-and-done thing is a disaster for actual discipleship and Christ-following. And it's not just those e-word people that are the problem; all corners of Christianity, including the mainline, have severe problems grasping all this.
The call is not to volunteer to die; the call is, like Jesus, to give your whole life, your inside and out life, all of you. And that goes on every day of your life.
And that's really hard.