I've found two statements about fasting by Gandhi (Vol.61). These are reproduced here without comment.
STATEMENT ON FAST
By M.K. Gandhi in [April 30, 1933], published in The Harijan, under the title, “Fast for Purification”.
A tempest has been raging within me for some days. I have been struggling against it. On the eve of the ‘Harijan Day’ the voice became insistent, and said, ‘why don’t you do it?’ I resisted it. But the resistance was vain. And the resolution was made to go on an unconditional and irrevocable fast for twentyone days, commencing from Monday noon the 8th May and ending on Monday noon the 29th May.
As I look back upon the immediate past, many are the causes too sacred to mention that must have precipitated the fast. But they are all connected with the great Harijan cause. The fast is against nobody in particular and against everybody who wants to participate in the joy of it, without for the time-being having to fast himself or herself. But it is particularly against myself. It is a heart-prayer for the purification of self and associates, for greater vigilance and watchfulness. But nobody who appreciates the step about to be taken is to join me. Any such fast will be a torture of themselves and of me.
Let this fast, however, be a preparation for many such fasts to be taken by purer and more deserving persons than myself. During all these months since September last, I have been studying the correspondence and literature and holding prolonged discussions with men and women, learned and ignorant, Harijans and non-Harijans. The evil is far greater than even I had thought it to be. It will not be eradicated by money, external organization and even political power for Harijans, though all these three are necessary. But to be effective, they must follow or at least accompany inward wealth, inward organization and inward power, in other words, self-purification. This can only come by fasting and prayer. We may not approach the God of Truth in the arrogance of strength, but in the meekness of the weak and the helpless.
But the mere fast of the body is nothing without the will behind it. It must be a genuine confession of the inner fast, an irrepressible longing to express truth and nothing but truth. therefore, those only are privileged to fast for the cause of truth who have worked for it and who have love in them even for opponents, who are free from animal passion and who have abjured earthly possessions and ambition. No one, therefore, may undertake, without previous preparation and discipline, the fast I have foreshadowed.
Let there be no misunderstanding about the impending fast. I have no desire to die. I want to live for the cause, though I hope I am equally prepared to die for it. But I need for me and my fellow-workers greater purity, greater application and dedication. I want more workers of unassailable purity. Shocking cases of impurity have come under my notice. I would like my fast to be an urgent appeal to such people to leave the cause alone.
I know that many of my sanatanist friends and others think that the movement is a deep political game. How I wish this fast would convince them that it is purely religious.
If God has more service to take from this body, He will hold it together despite deprivation of earthly food. He will send me spiritual food. But He works through earthly agents, and everyone who believes in the imperative necessity of removing untouchability will send me the food I need, by working to the best of his or her ability for the due and complete fulfilment of the pledge given to Harijans in the name of caste Hindus.
Let co-workers not get agitated over the coming fast. They should feel strengthened by it. They must not leave their post of duty; and those who have temporarily retired for much needed rest or for being cured of ailments are as much at the post as healthy workers serving in their respective quarters. No one should come to me unless it be for necessary consultation on matters connected with the movement.
It is, I hope, needless for me to pray to friends that they will not ask me to postpone, abandon or vary the approaching fast in any way whatsoever. I ask them to believe me that the fast has come to me literally as described above. I, therefore, ask friends in India and all the world over to pray for me and with me that I may safely pass through the ordeal and that, whether I live or die, the cause for which the fast is to be undertaken may prosper.
And may I ask my sanatanist friends to pray that, whatever be the result of the fast for me, the golden lid that hides Truth may be removed?
ALL ABOUT THE FAST
By M.K.Gandhi in Harijan, 8 July 1933
It is, perhaps, meet that the very first writing for the Press I should attempt after the fast should be for the Harijan, and that in connection with the fast. God willing, I hope now to contribute my weekly quota to the Harijan as before the fast. Let no one, however, run away with the idea that I have regained my pre-fast capacity for work. I have still to be very careful how I work. Correspondents will, therefore, have mercy on me. They should know that for a while yet I shall be unable to cope with all their letters. Whatever they may have for my special attention will have still to wait for some time, probably yet another month. Who knows what will happen a month hence? We are short-lived and do not know even what will happen the next moment. Then what can one say about the ambitions of a Harijan worker like myself? To those who buy and read Harijanbandhu in a spirit of service, my advice is that they should not wait for my writings and opinions. The way for rendering service to Harijans is quite clear. The field is vast. Harijanbandhu endeavours to give an idea of the week’s activities. It also attempts to indicate what needs to be done, what can be done and how it is to be done. From that all could find one or the other way of service. Then where is the need of my writing or opinion? If I am tempted to write about it, it is only for my own satisfaction. I have to write only when I have something to say or explain to the readers. I hope readers won’t be disheartened and will maintain their relations with Harijanbandhu irrespective of whether I have something to write or not and whether I have the strength and the leisure.
Now for the fast.
The first question that has puzzled many is about the Voice of God. What was it? What did I hear? Was there any person I saw? If not, how was the Voice conveyed to me? These are pertinent questions.
For me the voice of God, of Conscience, of Truth or the Inner Voice or ‘the still small Voice’ mean one and the same thing. I saw no form. I have never tried, for I have always believed God to be without form. One who realizes God is freed from sin for ever. He has no desire to be fulfilled. Not even in his thoughts will he suffer from faults, imperfections or impurities. Whatever he does will be perfect because he does nothing himself but the God within him does everything. He is completely merged in Him. Such realization comes to one among tens of millions. That it can come I have no doubt at all. I yearn to have such realization but I have not got it yet and I know that I am yet very far from it. The inspiration I had was quite a different thing. Moreover, many get such inspiration quite often or at some time. There is certainly need for a particular type of sadhana1 to obtain such inspiration. If some efforts and some sadhana are necessary even to acquire the ability to have the commonest thing, what wonder if efforts and sadhana are needed to get divine inspiration? The inspiration I got was this: The night I got the inspiration, I had a terrible inner struggle. My mind was restless. I could see no way. The burden of my responsibility was crushing me. But what I did hear was like a Voice from afar and yet quite near. It was as unmistakable as some human voice definitely speaking to me, and irresistible. I was not dreaming at the time I heard the Voice. The hearing of the Voice was preceded by a terrific struggle within me. Suddenly the Voice came upon me. I listened, made certain that it was the Voice, and the struggle ceased. I was calm. The determination was made accordingly, the date and the hour of the fast were fixed. Joy came over me. This was between 11 and 12 midnight. I felt refreshed and began to write the note about it which the reader must have seen.
Could I give any further evidence that it was truly the Voice that I heard and that it was not an echo of my own heated imagination? I have no further evidence to convince the sceptic. He is free to say that it was all self-delusion or hallucination. It may well have been so. I can offer no proof to the contrary. But I can say this—that not the unanimous verdict of the whole world against me could shake me from the belief that what I heard was the true voice of God.
But some think that God Himself is a creation of our own imagination. If that view holds good, then nothing is real, everything is of our own imagination. Even so, whilst my imagination dominates me, I can only act under its spell. Realest things are only relatively so. For me the Voice was more real than my own existence. It has never failed me, and for that matter, anyone else.
And everyone who wills can hear the Voice. It is within everyone. But like everything else, it requires previous and definite preparation.
The second question that has puzzled many is whether a fast in which an army of doctors watch and guide the fasting person, as they undoubtedly and with extraordinary care and attention watched and guided me, when he is coddled in various other ways as I was, could be described as a fast in answer to the call of the Inner Voice. Put thus, the objection seems valid. It would undoubtedly have been more in keeping with the high claim made for the fast, if it had been unattended with all the extraordinary, external aids that it was my good fortune or misfortune to receive.
But I do not repent of having gratefully accepted the generous help that kind friends extended to me. I was battling against death. I accepted all the help that came to me as godsend, when it did not in any way affect my vow.
As I think over the past, I am not sorry for having taken the fast. Though I suffered bodily pain and discomfort, there was indescribable peace within. I have enjoyed peace during all my fasts but never so much as in this. Perhaps, the reason was that there was nothing to look forward to. In the previous fasts there was some tangible expectation. In this there was nothing tangible to expect. There was undoubtedly faith that it must lead to purification of self and others and that workers would know that true Harijan service was impossible without inward purity. This, however, is a result that could not be measured or known in a tangible manner. I had, therefore, withdrawn within myself.
The nature of the fast deserves some more consideration. Was it mere mortification of the flesh? I firmly believe that a fast taken for mortification of the flesh does some good from the medical point of view; apart from that it produces no particular effect. I know my fast was not at all meant for the mortification of the flesh. Nor was I ready for it. The time of the fast was beyond my imagination. From the letters then written to friends it is clear that I did not foresee any immediate fast. For me, this fast was a supplication or prayer to God coming from the depth of my heart. The fast was an uninterrupted twenty-one days, prayer whose effect I can feel even now. I know now more fully than ever that there is no prayer without fasting, be the latter ever so little. And this fasting relates not merely to the palate, but all the senses and organs. Complete absorption in prayer must mean complete exclusion of physical activities till prayer possesses the whole of our being and we rise superior to, and are completely detached from, all physical functions. That state can only be reached after continual and voluntary crucifixion of the flesh. Thus all fasting, if it is a spiritual act, is an intense prayer or a preparation for it. It is a yearning of the soul to merge in the divine essence. My last fast was intended to be such a preparation. How far I have succeeded, how far I am in tune with the Infinite, I do not know. But I do know that the fast has made the passion for such a state intenser than ever.
Looking back upon the fast, I felt it to have been as necessary as I felt it was when I entered upon it. It has resulted in some revelations of impurities among workers of which I had no knowledge whatsoever, and but for the fast I would never have gained that knowledge. All the letters that have come under my notice go to show that it has led to greater purification among the workers. The fast was meant not for the purification of known workers only who had been found wanting, but for all the workers, known and unknown, in the Harijan cause. Nothing probably could have brought home to the workers so well as this fast the fact that the movement is purely religious in the highest sense of the term, to be handled in a religious spirit by workers of character above reproach.
The work of removal of untouchability is not merely a social or economic reform whose extent can be measured by so much social amenities or economic relief provided in so much time. Its goal is to touch the hearts of the millions of Hindus who honestly believe in the present-day untouchability as a God-made institution, as old as the human race itself. This, it will be admitted, is a task infinitely higher than mere social and economic reform. Its accomplishment undoubtedly includes all these and much more. For it means nothing short of a complete revolution in the Hindu thought and the disappearance of the horrible and terrible doctrine of inborn inequality and high-and-lowness, which has poisoned Hinduism and is slowly undermining its very existence. Such a change can only be brought about by an appeal to the highest in man. And I am more than ever convinced that that appeal can be made effective only by self-purification, i.e., by fasting conceived as the deepest prayer coming from a lacerated heart.
I believe that the invisible effect of such fasting is far greater and far more extensive than the visible effect. The conviction has, therefore, gone deeper in me that my fast is but the beginning of a chain of true voluntary fasts by men and women who have qualified themselves by previous preparation for them and who believe in prayer as the most effective method of reaching the heart of things. How that chain can be established I do not know as yet. But I am striving after it. If it can be established, I know that it will touch, as nothing else will, the hearts of Hindus, both the opponents of reform and the Harijans. For the Harijans have also to play their part in the movement no less than the reformers and the opponents. And I am glad to be able to inform the reader that the Harijans have not been untouched by the fast. A number of letters received from abroad suggest that even there many hearts have awakened. If an imperfect fast by a man like me could create such awakening, who could then estimate how great and far-reaching the result would be if innocent men and women unassumingly, without any hope of medical or other aid and without one or the other concession, sacrifice their lives in an unbroken chain of fasts?