Riyad as-Salihin 108

Hadīth explanation: The longer a person lives while being obedient to Allah, the closer he becomes to Allah, because every good deed that he does in his long life brings him closer to Allah. Hence, the best of people is the one who attained these two: long life and good deeds. Having a long life is not good for a person unless his deeds are good and are done in obedience to Allah.

Sometimes, a long life could be evil for someone and a source of harm for him, as mentioned in another Hadīth, where the Prophet (may Allah's peace and blessings be upon him) was asked: "Who is the best of people?"

He said: "The one who lives long and his deeds are good." He was then asked: "And who is the worst of people?" He said: "The one who lives long and his deeds are bad" [Abu Dawūd and At-Tirmidhi; classified as Sahīh by Al-Albān].

Allah, the Almighty, says: {And let not those who disbelieve ever think that when We extend their time, it is good for them. We only extend it for them so that they may increase in sin, and for them is a humiliating punishment} [Sūrat Āl-‘Imrān: 178]. The fact that Allah gives those disbelievers respite in terms of a long life, sustenance, health, children, and wives, is not good for them; rather it is bad for them - we seek refuge in Allah from that - because they increase in sin thereby.

At-Tayyebi (may Allah have mercy on him) said: "Times and hours (to a person) are like the capital of a trader, so he should trade in what yields profit. The more capital he invests, the more profit he makes. Whoever works for what benefits him, wins and attains success; and whoever wastes his capital, incurs an evident loss."