A negative thinker sees difficulty in every opportunity, A positive thinker sees opportunity in every difficulty.

Bear sorrows and calamaties patiently, otherwise you will never be happy.

- Ali [Radhi Allah Anhu]

Joy is not the absence of difficulties, but the presence of Allah SWT.

Ibn Hazam al-Andalusee Rahimahullah mentions:

A man who is a miser with his knowledge is worse than a man who is a miser with his money, for the money-miser is afraid of using up what he possesses but the knowledge-miser is being mean with something which does not get used up and is not lost when it is given away.
al-Akhlaaq was-Siyar – Ibn Hazam al-Andalusee