Stand in the night prayer and sleep. Fast some days and do not fast some days.
'Abdullah ibn Umar, may Allah be pleased with them, is reported to have said: the Messenger of Allah (may the peace and blessings of Allah be upon him) said, "I have been informed that you observe fast continuously and recite (the whole of the Qur'an) every night." I said, "Messenger of Allah! It is right, but I covet thereby nothing but good," whereupon he (may the peace and blessings of Allah be upon him) said: "Then observe fasts like the fasting of Prophet Dawud as he was the most ardent worshipper of Allah; recite the Qur'an once every month." I said, "O Prophet of Allah! I am capable of doing more than that." He said, "Then recite it (the complete Qur'an) in every twenty days." I said, "O Prophet of Allah I am capable of reciting more than that." He said, "Then recite it once in every ten days." I said, "O Prophet of Allah! I am capable of reciting more than that." He said, "Then recite it once in every seven days, but do not recite in less than that." The Prophet of Allah also said to me, "You do not know, you may have a longer life". When I grew old I wished I had availed myself of the concession (granted to me by) the Prophet of Allah.
In another narration 'Abdullah is reported to have said: the Messenger of Allah (may the peace and blessings of Allah be upon him) said, "The best fasting with Allah is that of (Prophet) Dawud, and the best prayer with Allah is that of Dawud for he would sleep half of the night and stand for prayer for the third of it and (then) would sleep sixth part of it; he observed fast one day and leave off the other. He would not flee on meeting the enemy".
Moderation in all matters is the approach of Islam, it is a realistic approach based on moderation in everything. Then there should be neither negligence nor transgressing the limits. As well there shall be harm or reciprocating harm.
The right of the body is to give it some rest, to respond to its sexual desires moderately, feed it with the permissible foods and beverages without extravagance, to protect it from the severity of heat and cold without overburdening oneself, to care for the health so as to avoid the diseases and to be able to function satisfactorily. To wear the permissible adornment as feasible; for it is a part of the chivalry, on which every honored man should be keen.
The right of the eye is to let it sleep; therefore the Prophet singled it out after he mentioned the body while it is a part of the body; this is for the sake of confirmation.
Allah has made sleeping a rest for the human, so that no man or animal can dispense with it. It is one of the greatest blessings.
Worship is not limited in the prayer and fasting. Rather, every useful movement and useful work, fruitful meeting, innocent promenade, and permissible entertainment may be considered an act of worship.
If a person is cut off from the other people, how can he fulfill his duty to his relatives, friends and neighbors, and all these rights to them.
Allah has enjoined His slaves to know each other and to cooperate with each other on righteousness and piety, so how can he do that while he is secluded in his place of worship, or isolated is in his house, fasting the day and performing the night prayer, but he does not visit the people or welcome them in his house.