And if Lord Allah’s Bounty and Mercy had not upon you, a fraction of them would have aimed to lead you astray, while they are not straying except themselves, and they don’t harm you in any way; and Allah has sent down the Book and Wisdom upon you, and He has taught you what you don't know, and Allah’s Bounty upon you is the Great.
It is told to Messenger in verses 17: 73-75: "Indeed if hypocrites could, they would have seduced you away from the Book We revealed to you for forging about Us something else, and then they would have taken you as an intimate friend. And if We had not braced you, you would have almost inclined to them a little; then, We would have made you taste double punishment in this life and Hereafter, then you would not find any helper against Us".
Verses 4: 105-113 were revealed in connection with an incident that happened in Medina during the Messenger’s time. One man named Tha’math who belonged to the Banu-Safar tribe stole a shield of an Ansari (Believer at Medina who accepted Islam and helped the believers migrated from Mecca with Messenger). When the owner started to enquire about it, Tha’math entrusted the shield to one of his Jewish friends. The owner suited the case before Messenger and told his doubt upon Tha’math. But Tha’math plotted with his family, relatives, and attributed it to that Jewish person. While the trial was undergone it was declared that the Jew was innocent. But Tha’math and his family argued: “He is a Jew who rejects the Truth and Messenger. So, his argument shouldn’t be accepted, and we are the believers and so our argument should be trusted". They wanted Messenger to judge in favor of them. At the first look, there was a reason to keep doubt upon the Jew and to judge in favor of Tha’math. But by revealing verses 4: 105-113 Lord commanded the Messenger to judge with the Truth among mankind without showing any discrimination and to seek forgiveness to Lord for the offense that they had doubted the Jewish person.
Today different groups of the Arabic Quran reading Fujjar are the true disbelievers mentioned in 520 places in the Book. But they are considering other people such as Jains, Buddhists, Hindus, Jews, and Christians as disbelievers. It is happening so because the Fujjar are following and are commanding others to follow the books written by the pseudo-prophets and hypocrites. Only one in a thousand becomes a believer who will judge in his individual, family, and social life with Adhikr as explained in verses 5: 44, 45, and 47. See explanation 2: 62 and 10: 57-58.