Why do some religious teachers use death as a tool to scare people into taking up religious practice?
Question: I have seen that spiritualists often have a standard message: material life is temporary with death possible at any time, so we should enquire about eternal life without delay. Why do they use death as a tool to scare people into taking up religious practice? Anyway, nobody can do that to me because I am not afraid of death.
Answer: I appreciate your concern and would like to present a few thoughts for your consideration.

Moreover, this bravado of being unafraid of death generally lasts only till one is face-to-face with imminent death. Then one fearfully and desperately tries everything possible to avoid death. But, by then, it’s too late.

Spiritualists live in harmony with God by chanting His holy names and offering their love to Him and so they experience peace and joy even in this life. Consequently, they truly value life: not the illusory life wasted in pursuing temporary pleasures, but the real life led in loving harmony with God. And they value death too; death reminds them of the urgency of reclaiming their eternal lives.
Most people are so captivated by hopes of temporary pleasures that they neglect their right to eternal life. So, just as a doctor is duty-bound to alert a cancer-afflicted patient about the disease’s future course, a spiritualist feels duty-bound to alert mortality-afflicted people about their imminent deaths. This is not a scaring technique, but an alerting technique. Fear of death doesn’t spoil the joy of life; rather it points the way to the real joy of life.