"Drink not the third glass, which thou canst not tame, when once it is within thee"

This quote by George Herbert is a caution against overindulgence in alcohol. He is warning against drinking too much, as it can lead to a loss of control. The third glass is a metaphor for the point at which one has actually had too much to consume and can no longer manage their actions. Herbert is cautioning that when this point is reached, it is far too late to reverse. He is suggesting that it is better to be knowledgeable about one's limitations and to not press them too far. This quote is a tip to be conscious of just how much one drinks and to not let it leave hand. It is a suggestion to be aware of the consequences of overindulgence and to take responsibility for one's actions.