Yes, Marx is not wrong when he says that religion is the opium of the people; it has been used that way. Not that religion as such is REALLY so, but religion has been used as an opium. Then people can be drugged.
Never bother about explanations. See the fact, and be aware of the fact, and don't be too concerned about explanations. Otherwise you will go on and on: you did something wrong in your past life, that's why you are so violent, aggressive, full of anger. But have you never asked the other question? -- "Why did I do something wrong in the past life?" Then they will say, "Even further back you did some wrong"; but that goes on and on. The question is: why, in the first place, did you do wrong in your first life? There is no explanation -- unless God Himself made you in such a way that you had to do something wrong. But then God is the culprit, you are not. Why should you suffer? Let Him suffer if He has committed a mistake.
These explanations are poor efforts to console oneself. Somebody dies and you are hurt, and you are in much pain, and you want somebody to console you, and somebody comes to console you -- because wherever there is demand there is supply. That is an economic law, it applies everywhere. If you are crying and weeping, some foolish, stupid person is bound to come, and he will say, "Don't cry. The soul is immortal." Now, that doesn't make any change. Your wife has died, and you cannot make love to your dead wife. The problem is there: you will miss her. The immortal soul cannot cook food for you tomorrow. And you have to look after your children; the immortal soul is not going to come.
But somebody says, "The soul is immortal"; it gives a sort of consolation: "So she has not died really. So she must be somewhere and there is a possibility to meet someday, somewhere, and it will be good." And you start dreaming, and it consoles. But this explanation is like a tranquilizer, a sedative, like alcohol; it intoxicates you.
If somebody has died and you are in pain, what do I say to you? I say: don't ask for explanations. Look at this pain. Death has happened; watch it. It has hurt you deeply; watch it, beware. Be aware, be mindful of how fragile life is, how everything ends. Just see the flux-like phenomenon of life, the momentary dream-like existence. Just see, and don't try to explain, and don't try to escape, and don't try to avoid, and don't try to get occupied somewhere else. Just look: death has happened, you are sad, great sorrow has happened to you; look into it. And by watching and becoming aware of it, much will be revealed to you. The sorrow, the sadness will disappear -- and with it will disappear all attachments, because you will be able to see that all attachment brings sorrow. It is not the death of your wife that you are sorry for. It is not because of death. If she had been somebody else's wife, there would have been no problem. She was your wife. It is not the question of death that you are troubled with. Some part of your being is snatched away -- you had become too attached -- you feel uprooted. You will feel a gap in your heart, an empty space.
Watching the sorrow that death brings, you will become aware that behind the sorrow is not death but attachment. And seeing the facticity of attachment, you will relax, you will become a little loose in your attachments. Next time death happens there will not be so much sorrow. And one day comes when death happens and there is no sorrow. You know this is how things are, you have accepted it. You have known the reality of life: that it ends in death. And there is nothing else to do. You have become aware.