1. When Christians are diagnosed with a life-threatening condition, they generally seek medical treatment. Some atheists mock their apparent fear of death.
It's a mark of how mindlessly spiteful some atheists are that they gloat over Christians who, in their minds, are inconsistent about death. "You're in the same sinking boat, with the sharks circling. Woo Hoo!"
Is that something to be gleeful about?
2. The insinuation is that fearful Christians are inconsistent because faith means pretending to know something you don't or belief without evidence, so when make-believe and wishful thinking collide with reality, inconsistencies emerge.
Let's unpack this allegation in relation to fear of death:
i) Some professing Christians are guilty of wishful thinking. The charismatic movement often fosters that mentality.
ii) There are theological traditions that cultivate fear of death. Old-fashioned Catholicism. Decisional evangelism.
iii) There are nominal Christians who don't believe in the afterlife.
iv) There are genuine Christians who haven't given much thought to death. In the past, death was pervasive, so you couldn't avoid contemplating your own demise. But with the advent of modern medicine and nursing homes, it's much easier to keep death in the back of our minds. We don't see nearly as much death as our forebears did. It's rare for our friends and loved ones to die young. Increasingly rare for the elderly to die in the homes of grown children. We don't have that chronic reminder.
v) There's a difference between intellectual preparation for death and emotional preparation for death.
vi) Some Christians resist death because they enjoy life. That's not necessarily an ungodly attitude. Life is a gift, to be cherished and made the most of.
vii) Death is supposed to be naturally fearful. That's what makes it punitive.
viii) Some Christians resist death because they have duties to dependents. They don't wish to desert their dependents. That's a godly motive.
ix) Some Christians look forward to death.
Different people fear death for different reasons:
Fear of dying
For some people, it's not what happens after death that they fear, but the process of dying. Some Christians look forward to the aftermath, but fear the process.
Fear of oblivion
People who deny the afterlife fear death because they fear the prospect of oblivion. For some people, that's more terrifying than hell.
Fear of punishment
Some people fear death because they fear hell. Although classic Protestant theology has diminished Christian fear of hell, there are theological traditions that cultivate fear of death, even for believers, viz. Islam, old-fashioned Catholicism, folk fundamentalism.
Fear of dismal afterlife
Historically, some heathens feared death because they viewed the afterlife as a state of deprivation. A shadow of life on earth.
Fear of the unknown
There's a difference between knowledge by acquaintance and knowledge by description. Unless you've had a near-death experience (I haven't), you have no direct knowledge of what it's like to die or what awaits you on the other side. And even NDEs are limited in that regard.
Moreover, the stakes in dying are uniquely high. You have everything to lose if you're wrong.
It is only natural to be afraid of something that potentially threatening if you lack firsthand experience that there's nothing to fear.
This can be true even if you have good evidence for what you believe. Beliefs based on personal experience have a sense of psychological certainty that secondhand knowledge lacks. That's despite the fact that secondhand knowledge can be more reliable than fallible memories about personal experience. Yet they lack that sense of certitude.
Finally, there are situations that make it easier for die. The simple fact that death is unavoidable makes it easier for Christians to face the prospect of death.
For Christians who've lost loved ones, the prospect of reunion sweetens the prospect of death. There's less here to keep them here. Much of what they value has gone over to the other side.