It is easy to die for your religion, any idiot can do that.
However, it isn't easy to live for it. Living a holy life is far, far, far harder than dying.
A sacrifice is only a sacrifice if it is valuable in the eyes of the giver. In a way, it is relative. Remember the widow who gave all that she had, two copper pieces? A greater sacrifice than many other rich men who gave out of the abundance.
Therefore, in order to sacrifice your life, you must learn to love your life, to love yourself, not in the hedonistic sense, but in the spiritual sense, to see yourself as a person created in the image of God.
A sacrifice must also be done out of love: "Greater love has no one than this, that he lay down his life for his friends." (John 15:13). A sacrifice done out of hate isn't a sacrifice at all, it is spite. It must be done, voluntarily, out of friendship not because of compulsion or a self indulgent reward like virgins in heaven.
That is why I disagree with extremists and reports that describe themselves as martyrs.