What is the meaning of [Give a thief enough rope and he’ll hang himself]

If you give a bad person enough opportunity he will bring about his own
downfall.

There is a play on words in the proverb, for ‘rope’ has tow meanings: (a) a
length of stout cordage as used for hanging, which was a penalty of theft in
olden days; and (b) liberty of action. We can appreciate the second meaning
when we consider a tethered goat, which a long rope allows to feed on a larger
area of grass than does a short one, Hence we can reword the old proverb thus:
‘Give a thief enough chances to steal and he will become so overconfident that
he will get himself into jail.’

Figuratively the proverb can be used as follows:

> ‘That new member,’ said the secretary of the Golf Club, ‘has already
offended several other members with his rudeness. We can’t very well ask him
to resign so soon, can we?’

> ‘I suggest letting things take their course,’ was the reply. ‘Give him
enough rope and he’ll hang himself. When he’s offended the whole Club and
nobody will play with him, he’ll _have_ to resign.’