Mentioned in verses previous to this were some prayers made by good believers.
The first verse (195) appearing above reports that these prayers have been accepted and believers have been given the good news that great rewards have been marked for their good deeds. In the second and third verses (196-197), Muslims have been instructed not to be deceived by the apparent affluence and worldwide maneuvering of disbelievers for this is transitory and the punishment which follows in its wake is eternal.
The fourth verse (198) reasserts the promise of the lasting blessings of Paradise for Muslims who always keep fearing Allah.
The fifth verse (199) particularly mentions the great reward that awaits those Muslims who used to be from among the People of the Book but chose to embrace Islam as their faith.
Commentary
While explaining the statement لَأُكَفِّرَنَّ عَنْهُمْ سَيِّئَاتِهِمْ (I shall certainly write off their evil deeds) in Verse 195, Maulana Ashraf Ali Thanavi (رح) has restricted it to the forgiveness of sins and shortcomings relating to the fulfillment of the rights of Allah. The reason is that the Holy Prophet ﷺ has said in Hadith that debts are not included under the purview of this verse. The rule is that the person concerned or his heirs should pay off the debt or have it forgiven. There is no other alternative in this case unless Allah Almighty is especially generous for someone and puts it in the heart of the wronged party that they should relent and forgive. This would, then, be a different matter. In fact, with some, this would also be the case.
So, let us keep in mind that all sins are forgiven following Hijrah (Emigration) and Shahadah (Surrendering life in the way of Allah, martyrdom) but the forgiveness of debts and other rights of people (Huququl-` Ibad) has not been promised.
Allah said,
(So their Lord accepted of them), answered their invocation. Sa`id bin Mansur recorded that Salamah, a man from the family of Umm Salamah said, "Umm Salamah said, `O Messenger of Allah! Allah does not mention women in connection with Hijrah (Migration).' Allah sent down the Ayah,
(So their Lord accepted of them (their supplication and answered them), "Never will I allow to be lost the work of any of you, be he male or female.)
The Ansar say that Umm Salamah was the first woman to migrate to them." Al-Hakim collected this Hadith in his Mustadrak, and said, "It is Sahih according to the criteria of Al-Bukhari but they Al-Bukhari and Muslim did not collect it".
Allah's statement,
("Never will I allow to be lost the work of any of you, be he male or female,) explains the type of answer Allah gave them, stating that no deed of any person is ever lost with Him. Rather, He will completely reward each person for his or her good deeds. Allah's statement,
(You are (members) one of another) means, you are all equal in relation to gaining My reward. Therefore,
(those who emigrated), by leaving the land of Shirk and migrating to the land of faith, leaving behind their loved ones, brethren, friends and neighbors,
(and were driven out from their homes), when the Mushriks tormented them and forced them to migrate,
(and suffered harm in My cause), for their only wrong, to the people, was that they believed in Allah Alone. In similar Ayat, Allah said,
(and have driven out the Messenger and yourselves because you believe in Allah your Lord!) 60:1, and,
(And they had no fault except that they believed in Allah, the Almighty, Worthy of all praise!)
(and who fought and were killed (in My cause),) 3:195 refers to the highest rank there is, that one fights in the cause of Allah and dies in the process, with his face covered in dust and blood. It is recorded in the Sahih that a man said,
('O Messenger of Allah! If I was killed in Allah's cause, observing patience, awaiting Allah's reward, attacking, not retreating, would Allah forgive my sins' The Prophet said, `Yes.' The Prophet then asked the man, `What did you ask' When the man repeated the question, the Prophet said, `Yes, except for the debt, for Jibril conveyed this to me right now'.)
This is why Allah said here,
(verily, I will expiate from them their evil deeds and admit them into Gardens under which rivers flow), within Paradise, where there are rivers of various drinks: milk, honey, wine and fresh water. There is what no eye has ever seen, no ear has ever heard and no heart has ever imagined of delights in Paradise. Allah's statement,
(a reward from Allah) testifies to His might, for the Mighty and Most Great only gives tremendous rewards. Allah's statement,
(and with Allah is the best of rewards.") for those who perform good deeds.