This truth is first to be listened to then to be thought about. Reason, argue it out by all manner of means. The enlightened know no more than that. Know it for certain that you are in everything. That is why you should not hurt anybody, because in hurting them you hurt yourself. . . . [Lastly,] this is to be meditated upon. Think upon it. Can you realise there will come a time when everything will crumble in the dust and you will stand alone? That moment of ecstatic joy will never leave you. You will actually find that you are without bodies. You never had bodies.
I am One, alone, through all eternity. Whom shall I fear? It is all my Self. This is continuously to be meditated upon. Through that comes realisation. It is through realisation that you become a [blessing] to others. . . .
- Swami Vivekananda
The Complete Works of Swami Vivekananda/Volume 2/Practical Vedanta and other lectures/The Goal