Also noteworthy at this point is the mention of the death of Sayyidna 'Isa and Sayyidah Maryam, peace be upon both of them, as a supposition - although, the death of Sayyidah Maryam was no supposition at the time of the revelation of the Qur'an; it had already occured, in fact. The reason for this may either be the superimposition (Taghlib) of the desired subject, that is, since the real intent here was to describe the death of Sayyidna 'Isa as a supposition, the mention of his blessed mother was also made as a corollary of the same subject, even though, her death had already occured or, it can also be said that the expression means: The way We have made death take away Sayyidah Maryam, it lies within Our power to make it overtake Sayyidna Masih and the rest of the creation as well. And the statement: يَخْلُقُ مَا يَشَاءُ : (He creates what He wills - 5:17), is there to refute this particular base which Christians use to deify Sayyidna Masih because they reason out that his birth came to pass, against all rules of nature operative in this world, without a father and from the mother alone had he too been a human being, he would have been born through a mother and father both, very much in accordance with the natural law.
This one sentence answers the reasoning by saying that Allah has the most perfect and the most comprehensive power to create what He wills and how He wills. The same doubt has been removed in the verse: إِنَّ مَثَلَ عِيسَىٰ عِندَ اللَّهِ كَمَثَلِ آدَمَ (Surely, the case of 'Isa, in the sight of Allah, is like the case of Adam - 359) where it has been established that the creation of Sayyidna Masih عليه السلام as separate from the habitual law of nature cannot become an argument in favour of his being taken as God.
The reason lies in pondering that Allah Ta'ala did create Sayyidna Adam عليه السلام without a father and mother both. He has the power, all power, over everything. He is the Creator and the Master and the most worthy of worship. No one else can be associated with His Divinity as a partner or sharer.
يَا أَهْلَ الْكِتَابِ قَدْ جَاءَكُمْ رَسُولُنَا يُبَيِّنُ لَكُمْ عَلَىٰ فَتْرَةٍ مِّنَ الرُّسُلِ أَن تَقُولُوا مَا جَاءَنَا مِن بَشِيرٍ وَلَا نَذِيرٍ ۖ فَقَدْ جَاءَكُم بَشِيرٌ وَنَذِيرٌ ۗ وَاللَّهُ عَلَىٰ كُلِّ شَيْءٍ قَدِيرٌ
O people of the Book, Our Messenger has come to you making things clear to you after a gap between Messengers, lest you were to say, "There has not come to us a bearer of good news, and a warner."So, now there has come to you a bearer of good news, and a warner. And Allah is powerful over everything. 
The word, "fatrah" in: عَلَىٰ فَتْرَةٍ مِّنَ الرُّسُلِ (after a gap between Messengers) literally means to slacken, to become dormant or to suspend or to terminate an activity. Leading authorities in Tafsir have given this very meaning of fatrah in this verse. It signifies the suspension of the coming of prophets for a certain interval of time which is the period of time in between Sayyidna 'Isa عليه السلام and the Last of the Prophets, Sayyidna Muhammad al-Mustafa (SM).
Verification of the Gap
According to Sayyidna 'Abdullah ibn 'Abbas رضي الله عنه there is a period of one thousand and seven hundred years between Sayyidna Musa عليه السلام and Sayyidna 'Isa عليه السلام. During this whole period, prophets kept
coming with their missions without any gap. To Bani Isra'il alone, one thousand prophets were sent during this period not included in which are prophets who appeared among peoples other than Bani Isra'il . Then comes the period of only five hundred years between the birth of Sayyidna 'Isa عليه السلام and the appearance of the Holy Prophet (SM) as the Last Prophet. During this period, the usual chain of prophets remained discontinued. Therefore, this period is known as Fatrah or Gap. Before this, a longer period has never remained unvisited by prophets. (Qurtubi, with some explanation from the author).
There are other reports regarding the period of time between Sayyidna Musa and Sayyidna 'Isa عليه السلام, and that which is between Sayyidna 'Isa عليه السلام and the Last Prophet, Sayyidna Muhammad al-Mustafa (SM). The period of time indicated in these reports is either more, or less, but that does not affect the real purpose.
Imam al-Bukhari reports on the authority of Sayyidna Salman al-Farisi رضي الله عنه that there was a period of six hundred years between the time of Sayyidna 'Isa عليه السلام and the Last among Prophets (SM).During this entire period, no prophet was sent as confirmed by a Hadith in Mishkat, appearing there with reference to the Sahihs of al-Bukhari and Muslim, which reports that the Holy Prophet (SM)said : أنا أولى الناس بعيسى that is, 'Among people, I am the closest to 'Isa عليه السلام' He explained the meaning of his remark later in the Hadith when he said: ليس بيننا وبين نبي 'that is, 'No prophet was sent between the two of us.'
As for the three messengers mentioned in Surah Ya Sin (36), they were messengers sent by Sayyidna 'Isa عليه السلام who have been'called messengers (bearers of a message) in the literal sense.
About the appearance of Khalid ibn Sinan al-'Arabi during this gap as reported by some chroniclers, Tafsir Ruh al-Ma'ani says with reference to Shihab that his being a prophet is correct, but the period in which he came was earlier than Sayyidna 'Isa عليه السلام not after him.
Rulings concerning the Gap
Obviously, the verse seems to indicate the fate of the group of people who were not visited by any messenger or prophet or their deputies, nor did they have the religious laws of past prophets preserved with them; such people will be considered excusable and will deserve no punishment on the condition that such people should have not committed Shirk, the grave sin of ascribing partners in the Divinity of Allah. Therefore, Muslim jurists differ about rulings which apply to the people of Fatrah (gap), particularly about whether or not they will be forgiven.