The musician announced earlier this month that he was taking a hiatus from live performing in order to undergo treatment for an unspecified form of cancer.
Lord has now declared that the outpouring of love from Deep Purple's fans has been overwhelming.
He wrote on his blog: "Your responses to the news of my condition have touched my heart in a way that has truly helped to make my life a better place to be than it had occasionally threatened to become these last few weeks.
"Your wonderful messages wishing me strength and courage have given me even more strength and courage - and so much more than you can ever know."
Lord continued: "I read many of them with tears in my eyes, grateful for this cast-iron proof of the innate goodness of the human being, and grateful to every single one of you for your invaluable support."
Lord also said that his cancer treatment is going well, adding that he is "confident" he will survive the disease.
The rocker first joined in 1967 and played on well-known tracks such as 'Smoke On The Water' and 'Demon's Eye'.
Lord retired from Deep Purple in 2002, but has performed with the group on select dates in recent years.
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Watch Deep Purple perform 'Demon's Eye' below: