Too Much of a good thing
Too Much of a good thing : Phrases
Excess may do you harm.
The Oxford Dictionary of Quotations lists this phrase as proverbial and dates it from the late 15th century. Th earliest example that I can find of it in print is from Shakespeare's As You Like It, 1600:
Why then, can one desire too much of a good thing?
Come, sister, you shall be the priest and marry us.
Give me your hand, Orlando. What do you say, sister?
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