The history of the Sri Aurobindo Ashram until 1950 could be presented in three periods of 12 years: 1914 – first physical meeting of Sri Aurobindo and the Mother and the beginning of their collaboration. 1926 – descent of Overmind; the Mother takes charge of the Ashram. 1938 – Sri Aurobindo’s accident which takes him out of his seclusion; beginning of a decisive battle against asuric forces. 1950 – Sri Aurobindo leaves his body in order to continue his work from the subtle-physical plane, whilst the Mother strives on for the fulfillment of his object on earth: the manifestation of Supermind, which, in its turn, took place six years later in the earth’s subtle-physical layer.
By the end of 1950 Sri Aurobindo developed a kidney infection which did not appear serious at first. The sadhaks attending on him, among them some doctors, felt quite confident that he could heal the illness by sheer spiritual will-force as he had done so often in the case of disciples and devotees. But the illness became more and more serious. After the School Anniversary functions on 1 and 2 December were over, his fever rose dangerously in the afternoon of 3 December. December 4 brought some improvement, but when Sri Aurobindo was asked by a disciple, “Are you using your force to get rid of the disease?” his surprising answer was a plain “No”. When questioned “why”, he replied: “Can’t explain. You won’t understand.” Nirodbaran writes: “Here at last was the key to the mystery! That is why the disease had progressed step by step, marked by three clear stages in its downward path: the completion of Savitri, Darshan on November 24, and the School Anniversary, each stage followed by a deeper and deeper in-drawn condition. It was about one of the final stages that the Mother remarked, ‘Whenever I was there, I used to see him pulling down the Supramental Light.’ It was clear from this statement what Sri Aurobindo was busy with. He had shifted his gaze and concentration to something else which, to his view, must have been much more important than minding the afflictions of the body.”
On 5 December, at 1.26 in the morning Sri Aurobindo left his body. Dr. Sanyal who had been attending on Sri Aurobindo asked to call the Mother. He reports: “Almost immediately the Mother entered the room. She stood there, near the feet of Sri Aurobindo… Her look was so fierce that I could not face those eyes.” The Mother looked at Sri Aurobindo for half an hour in silent concentration and then she turned towards Dr. Sanyal: “Softly She came to me, touched my head, stilled my thoughts, quietened my mind. No trace of agony was left, I could think normally. I asked Her, ‘What is to be done, we have to arrange for the last offices.’ She quietly said, ‘He will be given Samadhi, under the Service tree, in the place where the giant maidenhair plants are arranged.’ ”
All the Ashram members and the public were informed and an endless line of sadhaks and devotees passed through Sri Aurobindo’s Room for a last darshan. A supramental Light was enveloping his body and preventing its decomposition. On 6 December the Mother said to Dr. Sanyal: “People do not know what a tremendous sacrifice He has made for the world. About a year ago, while I was discussing things I remarked that I felt like leaving this body of mine. He spoke out in a very firm tone, ‘No, this can never be. If necessary for this transformation I might go, you will have to fulfil our yoga of supramental descent and transformation.’ ”
On the third day too no signs of decomposition were observed. According to the Laws of Pondicherry, a French doctor had to be called to confirm this. On 9 December in the morning the supramental aura started gradually withdrawing from Sri Aurobindo’s body and in the evening the body was placed into a prepared samadhi under the Ashram Service Tree.
Later on, the Mother explained the reason for his departure:
“Sri Aurobindo has given up his body in an act of supreme unselfishness, renouncing the realisation in his body to hasten the hour of the collective realisation. Surely if the earth were more responsive, this would not have been necessary.
“When I asked him to resuscitate he clearly answered: ‘I have left this body purposely. I will not take it back. I shall manifest again in the first supramental body built in the supramental way.’ ”
Many Ashram members were shocked and the Mother had to use all her power and concentration to ward off the depression in the atmosphere. More than ever the sadhaks and devotees were required now to establish the inner contact and she asked them in a number of messages to feel Sri Aurobindo’s living Presence:
“To grieve is an insult to Sri Aurobindo who is here with us, conscious and alive.
“We must not be bewildered by appearances. Sri Aurobindo has not left us. Sri Aurobindo is here, as living and as present as ever and it is left to us to realise his work with all the sincerity, eagerness and concentration necessary.”
 To Thee Our Infinite Gratitude, p. 26
 Nilima – Glimpses of the Mother’s Life 2:205
 Nilima – Glimpses of the Mother’s Life 2:206
 Nilima – Glimpses of the Mother’s Life 2:207
 Nilima – Glimpses of the Mother’s Life 2:209
 Nilima – Glimpses of the Mother’s Life 2:212