Sri Aurobindo
Letters of Sri Aurobindo
Volume 3
We appreciate the spirit in which you have made the suggestion, but a meditation with you will not in the least strain the Mother, on the contrary it will have the opposite effect. So you need not hesitate to come, the Mother will give you a meditation for some time and it will rather rest than at all strain her.
As for the question about the illness, perfection in the physical plane is indeed part of the idea of the Yoga, but it is the last item and, so long as the fundamental change has not been made in the material consciousness to which the body belongs, one may have a certain perfection on other planes without having immunity in the body. We have not sought perfection for our own separate sake, but as part of a general 
change creating a possibility of perfection for others. That could not have been done without our accepting and facing the difficulties of the realisation and transformation and overcoming them for ourselves. It has been done to a sufficient degree on the other planes – but not yet on the most material part of the physical plane. Till it is done, the fight there continues and, though there may be and is a force of Yogic action and defence, there cannot be immunity. The Mother’s difficulties are not her own; she bears the difficulties of others also and those that come with the general action and working for transformation. If it had been otherwise, it would be a very different matter.