Commentary
Previous verses carried inducement to Jihad. The first verse from the present ones (123) which opens with the words: يَا أَيُّهَا الَّذِينَ آمَنُوا قَاتِلُوا ( O those who believe, fight those disbelievers who are near you) gives details, for disbelievers are spread out all over the world and any confrontation with them has to have some sort of functional sequence. The verse says that Jihad should first be waged against those of the disbelievers who were near. ` Being near' could be taken in terms of the place, that is, the disbelievers who live closer to home base should be fought against first. And it could also be understood in terms of relationship, that is, those who are near in kinship, parentage and other social bonds should be given precedence. This is because Islamic Jihad is essentially carried out in their interest and for their well being, therefore, when it comes to care and concern, kinsfolk have precedence - similar to the command given to the Holy Prophet ﷺ : وَأَنذِرْ عَشِيرَتَكَ الْأَقْرَبِينَ ﴿214﴾ (And warn your near relatives against the punishment of Allah - 26:214). He carried out the command by assembling people from his family and conveyed to them the Word of Allah as revealed to him. The circle then became larger. Keeping the same principle of near and far, confronted first, as compared to others, were disbelievers who lived in the vicinity of Madinah, such as Banu Qurayzah, Banu Nadir and the people of Khaibar. After that came the fight against the rest within the Arabian Peninsula. And after things were settled there, came the last command to fight the disbelievers of Byzantium that resulted in the expedition of Tabuk.
In the second sentence of verse 123: وَلْيَجِدُوا فِيكُمْ غِلْظَةً (and let them find severity in you), the word: (ghilzah) غِلْظَةً means severity or toughness. The sense is that the disbelievers must be confronted in a manner that would not allow them to take their adversary to be weak.
The sentence: فَزَادَتْهُمْ إِيمَانًا (they have been increased in faith by it) in verse 124 tells us that the reciting the verses of the Qur'an, pondering over them, and acting in accordance with their dictates makes one advance in faith. One feels changes for the better, the higher. When 'Iman increases, so does its light and sweetness. Once in this blissful state, one starts seeing obedience to Allah and His Rasul as easy. ` Ibadah becomes inviting. One can feel the very taste of it. Sins pose no problems, for one starts hating sins by his own nature. They tempt no more. In fact, they irritate and vex.
Sayyidna ` Ali ؓ has said, ` when 'Iman enters the heart, it is like a radiant dot. As 'Iman increases, its radiance increases, until the whole heart becomes blissfully radiant. Similarly, disbelief and hypocrisy start appearing on the heart first as a black dot. Then, with every increase in sin and disbelief, the dot keeps increasing in size until the whole heart turns black.' (Mazhari). For this reason, the noble Companions of the Holy Prophet ﷺ used to tell each other, ` let us sit together for a while and remind each other of things relating to our din دِین and 'akhirah so that it increases our 'Iman.'