Imagine this....
Your 70 years old. You've had a fairly long life, maybe longer than most where your from. You are a firm believer in the tenants of your religion. Then you get to thinking...hey, I did this once, that, some other pretty "bad" things in they eye's of your religious scholars (should they find out about it). Ah heck...to die in a Jihad is to be a Martyr, instant heaven.
...I'd prolly pack up my musket and head to war too.
Tumor