Despite it being one of the shortest chapters of the Qur’ān, so short that many opt to recite it when short on time and in need of—God forgive us—an express-Salāh, it contains within it guidance that is sufficient to transform our present life and hereafter as well. I speak of Sūrat al-Sharh, the Chapter of Expansion, and specifically the āyah فَإِذَا فَرَغْتَ فَانْصَب ; “So when you have finished your duties, devote yourself for worship.” 
This verse, however, cannot be truly appreciated in absence of its context, as this āyah begins with the letter “fā” which, in this context, is called فاء التفريع — “the letter of branching”. In other words, what comes after it is branching out from what is before it. So, the first step in understanding this principle is to understand its context.
Sūrat al-Sharh was revealed to the Prophet (sallAllāhu ʿalayhi wasallam) during one of the most difficult times in his life, in Makkah when much sorrow and sadness had filled his heart. In eight beautiful verses of this sūrah, Allāh reminds the Prophet (sallAllāhu ʿalayhi wasallam) of His countless favours upon him and speaks of matters with the purpose of alleviating stress from his heart and replacing sorrow with happiness and contentment.
1) “Did We not expand for you your chest?
2) And We removed from you your burden (sins);
3) Which weighed down your back?
4) And have We not raised high for you your fame?
5) For indeed, with hardship will be ease.
6) Indeed, with hardship will be ease.
7) So when you have finished your duties, devote yourself for worship.
8) And to your Lord direct your longing.”
In this sūrah, Allāh reminds the Prophet (sallAllāhu ʿalayhi wasallam) of three blessings that He had given him: 1) the expanding of his chest; 2) the removal of his burden; and 3) the raising of his fame. Before we proceed, it is essential to remind ourselves of a principle that the scholars state in this regard, that:
ما أعطاه الله -عز وجل- لنبيه –صلى الله عليه وسلم– فلأتباعه منه نصيب بقدر اتباعهم له
“Whatever Allāh has given to his prophet (sallAllāhu ʿalayhi wasallam), his followers also have a share of it according to how closely they follow his way.” 
So every Muslim can qualify himself for a portion of chest expansion, forgiveness of sins and raising of status, the amount of which depends on where we are in relation to his Sunnah, and thus the happiest of all people, and the purest from sins and the highest in status are those who are closest to the Sunnah with respect to knowledge, application and Daʿwah.
After making mention of the three gifts of Allāh upon His messenger and after stressing that relief is with difficulty, Allāh’s instructions to the Prophet (sallAllāhu ʿalayhi wasallam) are now issued, for the One who has given him all what was mentioned deserves to be thanked and this is how He is to be thanked: “So when you have finished your duties, devote yourself for worship. And to your Lord direct your longing.”
What is meant by “duties” in this āyah?
Some have said that it means: When you have finished your obligatory prayers, devote yourself for the night prayer, as was stated by Ibn Masʿūd.
Some have said that it means: When you have finished from the prayer, then devote yourself in Duʿā (i.e. just before one ends his prayer after the final tashahhud and salutations upon the Prophet (sallAllāhu ʿalayhi wasallam), to make a Duʿā before the taslim) as was stated by Ibn ʿAbbās, al-Dahhāk, Muqātil and others.
Some have said that it means: When you have finished fighting your enemies, then devote yourself for worship, as was stated by al-Hasan and Qatāda. 
Others have said that it means: When you have finished from your worldly duties, then devote yourself for the worship of Allāh, as was stated by Mujāhid, and was the favoured opinion of Ibn Kathīr, and seems to be the favoured opinion of Ibn Taymiya.
As is apparent, these opinions are close in meaning and they do not contradict one another, as Ibn Jarīr al-Tabari said that this āyah includes all of these meanings. What we take from this principle of an āyah is that the believer is a very busy person with no time to waste at all, constantly occupying himself with tasks which alternate between Dīn and Dunyā, a principle that treats the problem of “free time” which many complain of.
It was narrated that Ibn ʿAbbās came across two men who were wrestling, and so he said to them,
ما بهذا أُمرنا بعد فراغنا
“This isn’t what we were commanded to do in our spare time.” 
And ʿUmar b. al-Khattāb said,
إني أكره لأحدكم أن يكون خالياً سبهللاً لا في عمل دنيا ولا دين
“I hate seeing a person who is free, not doing anything with respect to his Dunyā or Dīn.” 
For this reason, the earlier generation of Muslims did not complain of free time. Never did they request holidays, times off, let alone retirement from the doing of good deeds and preparation for the life hereafter. It is not uncommon to come across some who, during their youth or bachelor years, display enormous activism whether pertaining to acts of worship, Daʿwah, study of Islām, teaching, setting up of projects and more, but when work, marriage or old age arrives their proactivity and enthusiasm begins to take a clear dip. But is there anyone who is too old to do good deeds?
“So when you have finished your duties, devote yourself for worship.”
Consider the work ethic and level of output in the professional world when money is on the line. Take a dentist for example, who sees patient after patient for eight or nine hours a day and does so consistently for years on end. If you ask him, “How many more patients do you intend on seeing in your life? How many more teeth do you intend on filling?” he wouldn’t be able to give you an answer, for there isn’t a specific limit in mind.
Consider the output of a builder who alternates from project to project for years on end. If you were to ask him, “How many more square metres of bricks are you looking to lay?” he wouldn’t be able to give you a response, for he intends on working on project after project without a specific limit in mind.
Consider the output of a pilot whose life consists of travel. The average person amongst us plans for weeks on end before a single long-distance journey that he needs to make, whereas the aeroplane pilot has dedicated his entire life to the fatigue of travel simply because money is involved, and understandably so. If you were to ask him, “how many more miles are you looking to travel?” again, he wouldn’t give you an answer, he has no limits in mind.
With all this said I ask: if this is our work ethic for our Dunyā because of 60/70 or so years of financial stability that we aspire for, how then should our work ethic be when eternity is on the line? Whoever still insists on holidays from the doing of good, or anticipates a retirement age from Daʿwah has not understood the road that leads to Jannah nor the purpose behind our existence.
In fact after the Arabian peninsula finally accepted Islām in its entirety after a lifetime that the Prophet (sallAllāhu ʿalayhi wasallam) spent in Duʿā, sacrifice, tears, sleepless nights and fear, Allāh’s commentary on Makkah’s conquest was not āyāt about retirement. Read with me:
إِذَا جَاءَ نَصْرُ اللَّهِ وَالْفَتْحُ * وَرَأَيْتَ النَّاسَ يَدْخُلُونَ فِي دِينِ اللَّهِ أَفْوَاجًا * فَسَبِّحْ بِحَمْدِ رَبِّكَ وَاسْتَغْفِرْهُ إِنَّهُ كَانَ تَوَّابًا
“When the victory of Allāh has come and the conquest. And you see the people entering into the religion of Allāh in multitudes. So glorify the Praises of your Lord, and ask His Forgiveness. Verily, He is the One Who accepts the repentance and Who forgives.”
After all what he did, these were some of the final āyāt which he received at a time where we would no longer be able to stand because of the bashing that he received, yet Allāh tells him that now you’ve completed your mission, remember Allāh.
“So when you have finished your duties, devote yourself for worship.”
Such a Muslim truly appreciates that Allāh most certainly did not send the prophets and messengers, aid them with scriptures, support them with miracles, nor did he create Jannah, gardens of eternal paradise, and Jahannam, everlasting chambers of torture, all for the purpose of play, entertainment and sole worldly pursuits. Impossible. It is because of this realisation that such a Muslim’s entire life is filled with countless shades of good deeds, alternating from one to the other. In fact, even when s/he participates in moments of innocent play and necessary entertainment, it is for the purpose of recharging the drive to continue along that path to Jannah, as Allāh said:
قُلْ إِنَّ صَلَاتِي وَنُسُكِي وَمَحْيَايَ وَمَمَاتِي لِلَّهِ رَبِّ الْعَالَمِينَ
Say, “Surely, my prayer, my sacrifice, my living and my death are all for Allāh, Lord of the worlds.” 
The fact that the opportunities to do good have been scattered all throughout the months of the year indicate beyond doubt that this is how Allāh wants us to be; a living explanation of the āyah: “So when you when you have finished your duties, devote yourself for worship”.
Consider the following.
Allāh has given us four months of the Islamic year that are ‘Hurum’ (sacred), where the believer is encouraged to try harder than before as good deeds within them are greater. One of them is the month of Rajab, then straight after it is the month of Shaʿbān which the Prophet (sallAllāhu ʿalayhi wasallam) would fast the majority of. After it is the month of Ramadān which is the greatest month of the year and within it is the greatest ten nights of the year—the last ten—and the greatest night of the year, Laylat al-Qadr.
After Ramadān is the month of Shawwāl wherein one is recommended to fast six days from it and whoever does so after having fasted Ramadān will be given the reward of someone who had fasted a lifetime. After Shawwāl is the month of Dhul-Qaʿda, another sacred month and one of the months of Hajj.
After Dhul-Qaʿda is the month of Dhul-Hijja, another sacred month, and is one of the months of Hajj as well and within it is the greatest ten days of the year—the first ten—and the greatest day of the year—the day of ʿArafah—the fasting of which expiates the present year’s sins as well as the sins of the following year. Hajj takes place within this month where those whose Hajj is accepted come out of all of their sins as if they were just born.
Then comes the month of Muharram, another sacred month, the fasting of which is the most rewarding after the month of Ramadān. Within this month is the day of ʿĀshūrā which erases a year’s worth of sins for those who fast during it.
Ponder over how the Islamic year begins, the month of Muharram, a month of worship, and how it ends, the month of Dhul-Hijja, another month of worship, and how these opportunities have been scattered throughout the months of the year. The very Islamic calendar indicates that our Lord is One who wants His servants to apply, “So when you when you have finished your duties, devote yourself for worship,” venerating Him and preparing for the Hereafter every second of the day.
Next, ponder over the life of the Prophet (sallAllāhu ʿalayhi wasallam) and how his entire biography was a living tafsīr of this āyah. Consider the sheer number of achievements within those 10 years that he spent in Madina.
In the first year after the immigration, he reached Qubā on the 8th day of the month of Rabīʿ al-Awwal and instantly built the Masjid of Qubā. He then made his way to the city of Madina on the 12th day of the same month where he built Masjid al-Nabawi, paired between the Muhājirūn and Ansār and created an agreement with the Jews.
In the second year after the immigration fasting, Zakāh, the ʿEid prayer and Zakāt al-Fitr were made an obligation. The rulings of Jihād became clear and the Qibla was changed. Then, in the same year, came the battle of Badr on the 17th day of Ramadān, then the eviction of the tribe of Qaynuqāʿ after their treachery.
In the third year after the Hijra, the battle of Uhud took place in the month of Shawwāl. The battle of Hamrā al-Asad also took place, in addition to the prohibition of alcohol.
In the fourth year, it was the two tragedies of al-Rajīʿ and Biʿr Maʿūna, then came the eviction of another tribe, al-Nadīr, after their attempt of assassinating the Prophet (sallAllāhu ʿalayhi wasallam). The āyāt of Hijāb were also revealed.
In the fifth year, it was the Battle of the Trench where thousands besieged Madina, then came the eviction of the final Jewish tribe, Quraydhā due to their treachery, then Hajj was obligated.
In the sixth year, an effort to make ʿUmrah was made but failed, a peace treaty of Hudaybiya was signed, the pledge of al-Ridwān took place and the Prophet (sallAllāhu ʿalayhi wasallam) communicated with the leaders of the world.
In the seventh year, the Jewish forts of Khaybar were conquered and ʿUmrah was embarked on.
In the eighth year, the battle of Muʿta took place, Makkah was conquered, the battle of Hunayn was engaged in and the Prophet (sallAllāhu ʿalayhi wasallam) besieged the city of al-Tā’if.
In the ninth year, the battle of Tabūk took place, then over 70 delegations made their way to Madina pledging allegiance to the Prophet (sallAllāhu ʿalayhi wasallam).
In the tenth year, the farewell pilgrimage took place and the Prophet (sallAllāhu ʿalayhi wasallam) prepared the army of Usāma b. Zayd.
In the eleventh year, the entire Arabian Peninsula had accepted Islām, but this would come at the cost of the health of the Prophet (sallAllāhu ʿalayhi wasallam), for he would—by this time—lose his ability to pray standing because of just how fatigued and hurt his body was. It was on this year that the ultimate calamity took place, on a Monday on the 12th of Rabīʿ al-Awwal during the Duha (forenoon) time, the Prophet (sallAllāhu ʿalayhi wasallam) would answer the call of his Lord and his blessed soul would depart, after a life that was a practical tafsīr of the Ayah:
“So when you when you have finished your duties, devote yourself for worship.”
This is how Allāh wants the Muslim to be and when we nurture this culture amongst our families and communities, this is when the Ummah will see change.
Every day that passes, a page from your life has been turned over, and again and again, until the pages run out. Therefore at the end of each day, after you tuck yourself into bed and just before you fall asleep, ask yourself: what did I put forward for my Hereafter today? Was I a slave of Allāh today? Did I make proper use of my time? Will this day witness for me or against me on the Day of Reckoning?
With all the above said, we must ask: if this is the rigorous lifestyle that the Qur’ān is suggesting—one of perpetual Duʿā, Salāh, activism, self-improvement, planning and building of one’s Hereafter—when does it come to an end? When does one rest?
Imām Ahmad was once asked the exact same question: “When will one truly rest?”
متى يجد المؤمن طعم الراحة؟
قال: إذا وضع رجله في الجنة
He responded, “Upon the first step he takes into Jannah.”
This is when the luggage of stress, fatigue and anxiety are dropped once and for all, never to be lifted again, where people will be heard saying:
الْحَمْدُ لِلَّهِ الَّذِي أَذْهَبَ عَنَّا الْحَزَنَ
“Praise to Allāh, who has removed from us all sorrow.” 
But up until you arrive there, measure your life on a daily basis with the āyah the reads:
“So when you have finished your duties, devote yourself for worship.”
 Al-Qur’ān, Sūrah 94, Ayah 7
 Ibnul Qayyim and AshShaatibi
 Zaadal Maseer fi ‘ilmit Tafseer
 Tafseer Al-Qurtubi
 Tafseer At-Tabari
 Tafseer Ibnu Katheer
 Majmoo’ AlFataawah
 Adwaa’ul Bayaan
 Al-Qur’ān, 110:1-4
 Al-Qur’ān, Sūrah 6, Ayah 162
 Al-Qur’ān, Sūrah 35, Ayah 34