Srimad Bhagavatam

påñöhe bhrämyad amanda-mandara-giri-grävägra-kaëòüyanän
nidräloù kamaöhäkåter bhagavataù çväsäniläù päntu vaù
yat-saàskära-kalänuvartana-vaçäd velä-nibhenämbhasäà
yätäyätam atandritaà jala-nidher nädyäpi viçrämyati

When the Supreme Personality of Godhead appeared as Lord Kürma, a tortoise, His back was scratched by the sharp-edged stones lying on massive, whirling Mount Mandara, and this scratching made the Lord sleepy. May you all be protected by the winds caused by the Lord's breathing in this sleepy condition. Ever since that time, even up to the present day, the ocean tides have imitated the Lord's inhalation and exhalation by piously coming in and going out. (Srimad Bhagavatam 12:13:2.)

PURPORT
At times we alleviate an itching sensation by blowing upon it. Similarly, Çréla Bhaktisiddhänta Sarasvaté Öhäkura explains, the breathing of the Supreme Personality of Godhead can alleviate the itching sensation within the minds of mental speculators, as well as the itching of the material senses of conditioned souls engaged in sense gratification. Thus by meditating on the windy breath of Lord Kürma—the tortoise incarnation—all categories of conditioned souls can be relieved of the deficiencies of material existence and come to the liberated, spiritual platform. One must simply allow the pastimes of Lord Kürma to blow within one's heart like a favorable breeze; then one will surely find spiritual peace.