Some people get confused when they try to combine between the religious ruling pertinent to the people of the book and between dealing with them. Most people don’t understand whether the people of the book are believers or not and if they were not believers, how can we deal with them?
If we want to understand this issue deeply, we need to divide this topic into two parts. The first part has to do with theology and to clarify this part we need to know the elements of faith which is the belief in God, His angels, His messengers, His books and the Last Day. Therefore whoever believes in all these elements is a believer and whoever denies any of it, is not a believer. In other words, for a believer he or she has to believe in all of God’s revealed books and all of His messengers and whoever denies even one messenger or one book is not deemed a believer even if he believes in the remaining elements of faith. This ruling applies on the people of the book who deny the prophethood of Prophet Muhammad and the book that was revealed on him (the Quran).
Same ruling applies on Muslims should they deny the prophethood of Moses or Jesus or denied the existence of the Torah or the Bible. One of the most all encompassing verses which combine all the elements of faith together says, “The Messenger has believed in what was revealed to him from his Lord, and [so have] the believers. All of them have believed in Allah and His angels and His books and His messengers, [saying], "We make no distinction between any of His messengers." And they say, "We hear and we obey. [We seek] Your forgiveness, our Lord, and to You is the [final] destination." 2:285
As for the second part, it has to do with how to deal with non Muslims especially if they are from the people of the book because they have an advantage over others. This advantage allows Muslims to marry from them and eat their slaughtered animals and one of the famous verses on this issue is “And do not argue with the People of the Scripture except in a way that is best, except for those who commit injustice among them, and say, "We believe in that which has been revealed to us and revealed to you. And our God and your God is one; and we are Muslims [in submission] to Him." 29:46
Therefore, there is no contradiction between someone being a disbeliever and between treating him good because being a disbeliever is a theological matter as disbelief in the Arabic linguistic means covering some elements of faith. The fact of someone being a disbeliever which is a theological matter does not contradict the necessity of dealing with him or her in a good manner. Prophet Muhammad (peace be upon him) dealt with disbelievers with wisdom, good manners and fine etiquette. God says, “Invite to the way of your Lord with wisdom and good instruction, and argue with them in a way that is best. Indeed, your Lord is most knowing of who has strayed from His way, and He is most knowing of who is [rightly] guided.” 16:125
The problem of those who misunderstand Islam is that they erroneously think that just because a person is a disbeliever, this theological fact gives them the permission of mistreating them and even shedding their blood.
This extreme thinking occurs due to concluding erroneous results that are built on sound introductions. And these erroneous results have nothing to do with the essential basis of good manners and coexistence that guide the relationship between Muslims and non Muslims.