Tafsir Ibn Kathir -> Surah At-Taubah -> The Order to speak the Truth

Allah sent His relief from the distress and grief that struck these three men, because Muslims ignored them for fifty days and nights, until they themselves, and the earth -- vast as it is -- were straitened for them. As vast as the earth is, its ways and paths were closed for them, and they did not know what action to take. They were patient for Allah's sake and awaited humbly for His decree. They remained firm, until Allah sent His relief to them since they told the Messenger of Allah the truth about why they remained behind, declaring that they did not have an excuse for doing so. They were requited for this period, then Allah forgave them. Therefore, the consequence of being truthful was better for them, for they gained forgiveness. Hence Allah's statement next,

﴿يَـأَيُّهَا الَّذِينَ ءَامَنُواْ اتَّقُواْ اللَّهَ وَكُونُواْ مَعَ الصَّـدِقِينَ ﴾

(O you who believe! Have Taqwa of Allah, and be with those who are true.) The Ayah says, adhere to and always say the truth so that you become among its people and be saved from destruction. Allah will make a way for you out of your concerns and a refuge. Imam Ahmad recorded that `Abdullah bin Mas`ud said that the Messenger of Allah said,

«عَلَيْكُمْ بِالصِّدْقِ فَإِن الصَّدْقَ يَهْدِي إِلَى الْبِرِّ، وَإِنَّ الْبِرَّ يَهْدِي إِلَى الْجَنَّةِ، وَلَا يَزَالُ الرَّجُلُ يَصْدُقُ وَيَتَحَرَّى الصِّدْقَ حَتَّى يُكْتَبَ عِنْدَ اللهِ صِدِّيقًا، وَإِيَّاكُمْ وَالْكَذِبَ فَإِنَّ الْكَذِبَ يَهْدِي إِلَى الْفُجُورِ وَإِنَّ الْفُجُورَ يَهْدِي إِلَى النَّارِ، وَلَا يَزَالُ الرَّجُلُ يَكْذِبُ وَيَتَحَرَّى الْكَذِبَ حَتَّى يُكْتَبَ عِنْدَ اللهِ كَذَّابًا»

(Hold on to truth, for being truthful leads to righteousness, and righteousness leads to Paradise. Verily, a man will keep saying the truth and striving for truth, until he is written before Allah as very truthful (Siddiq). Beware of lying, for lying leads to sin, and sin leads to the Fire. Verily, the man will keep lying and striving for falsehood until he is written before Allah as a great liar.) This Hadith is recorded in the Two Sahihs.

﴿مَا كَانَ لأَهْلِ الْمَدِينَةِ وَمَنْ حَوْلَهُمْ مِّنَ الاٌّعْرَابِ أَن يَتَخَلَّفُواْ عَن رَّسُولِ اللَّهِ وَلاَ يَرْغَبُواْ بِأَنفُسِهِمْ عَن نَّفْسِهِ ذَلِكَ بِأَنَّهُمْ لاَ يُصِيبُهُمْ ظَمَأٌ وَلاَ نَصَبٌ وَلاَ مَخْمَصَةٌ فِى سَبِيلِ اللَّهِ وَلاَ يَطَأُونَ مَوْطِئًا يَغِيظُ الْكُفَّارَ وَلاَ يَنَالُونَ مِنْ عَدُوٍّ نَّيْلاً إِلاَّ كُتِبَ لَهُمْ بِهِ عَمَلٌ صَالِحٌ إِنَّ اللَّهَ لاَ يُضِيعُ أَجْرَ الْمُحْسِنِينَ ﴾

(120. It was neither befitting for the people of Al-Madinah and the bedouins of the neighborhood to remain behind Allah's Messenger nor to prefer their own lives to his life. That is because they suffer neither Zama' nor Nasab, nor Makhmasah in the cause of Allah, nor did they take any step to raise the anger of disbelievers nor inflict any injury upon an enemy, but is written to their credit as a deed of righteousness. Surely, Allah wastes not the reward of the doers of good.)