Allah said,

[وَلَقَدْ نَعْلَمُ أَنَّكَ يَضِيقُ صَدْرُكَ بِمَا يَقُولُونَ - فَسَبِّحْ بِحَمْدِ رَبِّكَ وَكُنْ مِّنَ السَّـجِدِينَ ]

(Indeed, We know that your breast becomes tight because of what they say. So glorify the praises of your Lord and be of those who prostrate themselves (to Him).) meaning `We know, O Muhammad, that you are distressed by their insults towards you, but do not let that weaken your resolve or cause you to give up conveying the Message of Allah. Put your trust in Him, for He will suffice you and will support you against them. Keep yourself busy with remembering Allah, praising Him, glorifying Him, and worshipping Him (which means Salah, or prayer)' Hence Allah says:

[فَسَبِّحْ بِحَمْدِ رَبِّكَ وَكُنْ مِّنَ السَّـجِدِينَ ]

(So glorify the praises of your Lord and be of those who prostrate themselves (to Him)) Imam Ahmad reported from Nu`aym bin Hammar that he heard the Messenger of Allah say:

«قَالَ اللهُ تَعَالَى يَا ابْنَ آدَمَ لَا تَعْجَزْ عَنْ أَرْبَعِ رَكَعَاتٍ مِنْ أَوَّلِ النَّهَارِ أَكْفِكَ آخِرَه»

(Allah said, "O son of Adam! It is not too difficult for you to perform four Rak'at at the beginning of the day, (and if you do them,) I will take care of you until the end of it.'')

[وَاعْبُدْ رَبَّكَ حَتَّى يَأْتِيَكَ الْيَقِينُ ]

(And worship your Lord until the certainty comes to you) (15: 99). Al-Bukhari said: "Salim said, `(This means) death.''' This Salim is Salim bin `Abdullah bin `Umar. Ibn Jarir also recorded from Salim bin `Abdullah,

[وَاعْبُدْ رَبَّكَ حَتَّى يَأْتِيَكَ الْيَقِينُ ]

(And worship your Lord until the Yaqin comes to you.) He said, "Death.'' It is reported in the Sahih from Umm Al-`Ala'- one of the women of the Ansar - that when the Messenger of Allah entered upon `Uthman bin Maz`un after he had died, Umm Al-`Ala' said, "May the mercy of Allah be upon you, Abu As-Sa`ib. My testimony over you is that Allah has honored you.'' The Messenger of Allah said,

«وَمَا يُدْرِيكَ أَنَّ اللهَ أَكْرَمَهُ؟»

(How do you know that Allah has honored him) I said, "May my father and mother be sacrificed for you, O Messenger of Allah! If not him, then who else'' He said,

«أَمَّا هُوَ فَقَدْ جَاءَهُ الْيَقِينُ، وَإِنِّي لَأَرْجُو لَهُ الْخَيْر»

(As far as he is concerned, the death has come to him, and I hope for good for him.) This is evidence that the meaning of this Ayah,

[وَاعْبُدْ رَبَّكَ حَتَّى يَأْتِيَكَ الْيَقِينُ ]

(And worship your Lord until the certainty comes to you.) is that acts of worship, such as prayer and the like, are obligatory on man so long as his mind is sound, so he should pray according to his best ability. It was reported in Sahih Al-Bukhari from `Imran bin Husayn that the Messenger of Allah said:

«صَلِّ قَائِمًا، فَإِنْ لَمْ تَسْتَطِعْ فَقَاعِدًا، فَإِنْ لَمْ تَسْتَطِعْ فَعَلَى جَنْب»

(Pray standing, and if you cannot, then sitting, and if you cannot, then on your side.) From this we may understand that it is a mistake to interpret Yaqin (the certainty) as Ma`rifah ("spiritual knowing'') as some of the Sufis do. According to them, when one of them attains the level of Ma`rifah, they consider him to be free of these obligations. This is disbelief, misguidance and ignorance. The Prophets - peace be upon them - and their companions, were the most knowledgeable of people about Allah, about His rights, His attributes, and the glorification that He deserves. But at the same time, they were the people who worshipped Him the most, continuing in good deeds until the time they died. Therefore, what is meant by Yaqin here is death, as we have stated above. To Allah be praise and thanks. Praise be to Allah for His guidance. It is to Him that we turn for help and it is in Him that we put our trust. He is the One Whom we ask to help us to reach the best of circumstances, for He is the Most Generous and Kind. This is the end of the Tafsir of Surat Al-Hijr. Praise be to Allah, the Lord of all that exists.