You must not waste your health and free time: d0 not become remiss in performing deeds of obedience to your Lord because you depend on past good actions. Take advantage of your health and free time by working and striving. Remember that you cannot always make up for lost time and that sooner or later, you will rue those times that you have wasted away in idleness. Bazrjamhar said: "If work causes one to tire, then inactivity causes one to decay."
One of the wise said:
"Don’t spend your day doing something that will not benefit you and don’t let your wealth remain idle by not investing it in some project. For there is too little time in one’s life to throw it away on something useless, and one’s supply of money is too small not to invest it. So the wise one is too judicious to waste his time in nonsense and to spend his money in something that will not bring a return."
More profound than that is the saying of ‘Eesa (Jesus):
"Piety is in three: in speech, in sight, and in silence. Whoever’s speech is not in remembrance (of Allah) has spoken nonsense. Whoever looks without trying to learn a lesson has forgotten (his true purpose). And whoever’s silence is not accompanied with reflection has been heedless."