In the Quran, Mary, the mother of Jesus is described in 19:28 as يَاأُخْتَ هَارُونَ which can be interpreted in one of two ways: either as “O sister of Aaron” or as “O descendant of Aaron.”
[19:27] She came to her family, carrying him. They said, “O Mary, you have committed something that is totally unexpected. [19:28] “O descendant of Aaron, your father was not a bad man, nor was your mother unchaste.”
فَأَتَتْ بِهِ قَوْمَهَا تَحْمِلُهُ قَالُوا يَامَرْيَمُ لَقَدْ جِئْتِ شَيْئًا فَرِيًّا
يَاأُخْتَ هَارُونَ مَا كَانَ أَبُوكِ امْرَأَ سَوْءٍ وَمَا كَانَتْ أُمُّكِ بَغِيًّا
In the Arabic of the Quran, the terms father, mother, brother, sister can be used for both someone’s immediate family member or ancestral family member. The most notable example of this is with the term “the Children of Israel” used towards people who are descendants of Israel (Jacob).
[2:83] We made a covenant with the Children of Israel: “You shall not worship except GOD. You shall honor your parents and regard the relatives, the orphans, and the poor. You shall treat the people amicably. You shall observe the Contact Prayers (Salat) and give the obligatory charity (Zakat).” But you turned away, except a few of you, and you became averse.
وَإِذْ أَخَذْنَا مِيثَاقَ بَنِي إِسْرَائِيلَ لَا تَعْبُدُونَ إِلَّا اللَّهَ وَبِالْوَالِدَيْنِ إِحْسَانًا وَذِي الْقُرْبَىٰ وَالْيَتَامَىٰ وَالْمَسَاكِينِ وَقُولُوا لِلنَّاسِ حُسْنًا وَأَقِيمُوا الصَّلَاةَ وَآتُوا الزَّكَاةَ ثُمَّ تَوَلَّيْتُمْ إِلَّا قَلِيلًا مِنْكُمْ وَأَنْتُمْ مُعْرِضُونَ
Additionally, we also see similar language used for the believers towards Abraham whose son Ishmael was the descendent of the Arab people.
[22:78] You shall strive for the cause of GOD as you should strive for His cause. He has chosen you and has placed no hardship on you in practicing your religion—the religion of your father Abraham. He is the one who named you “Submitters” originally. Thus, the messenger shall serve as a witness among you, and you shall serve as witnesses among the people. Therefore, you shall observe the Contact Prayers (Salat) and give the obligatory charity (Zakat), and hold fast to GOD; He is your Lord, the best Lord and the best Supporter.
وَجَاهِدُوا فِي اللَّهِ حَقَّ جِهَادِهِ هُوَ اجْتَبَاكُمْ وَمَا جَعَلَ عَلَيْكُمْ فِي الدِّينِ مِنْ حَرَجٍ مِلَّةَ أَبِيكُمْ إِبْرَاهِيمَ هُوَ سَمَّاكُمُ الْمُسْلِمِينَ مِنْ قَبْلُ وَفِي هَٰذَا لِيَكُونَ الرَّسُولُ شَهِيدًا عَلَيْكُمْ وَتَكُونُوا شُهَدَاءَ عَلَى النَّاسِ فَأَقِيمُوا الصَّلَاةَ وَآتُوا الزَّكَاةَ وَاعْتَصِمُوا بِاللَّهِ هُوَ مَوْلَاكُمْ فَنِعْمَ الْمَوْلَىٰ وَنِعْمَ النَّصِيرُ
Also, the use of Adam as the father of the humans.
[7:27] O children of Adam, do not let the devil dupe you as he did when he caused the eviction of your parents from Paradise, and the removal of their garments to expose their bodies. He and his tribe see you, while you do not see them. We appoint the devils as companions of those who do not believe.
يَابَنِي آدَمَ لَا يَفْتِنَنَّكُمُ الشَّيْطَانُ كَمَا أَخْرَجَ أَبَوَيْكُمْ مِنَ الْجَنَّةِ يَنْزِعُ عَنْهُمَا لِبَاسَهُمَا لِيُرِيَهُمَا سَوْآتِهِمَا إِنَّهُ يَرَاكُمْ هُوَ وَقَبِيلُهُ مِنْ حَيْثُ لَا تَرَوْنَهُمْ إِنَّا جَعَلْنَا الشَّيَاطِينَ أَوْلِيَاءَ لِلَّذِينَ لَا يُؤْمِنُونَ
Another example can be found in 46:21 in reference to ‘Ād, the community that Hud was sent to. While ‘Ād is the name of the community, the origins of this name comes from the legendary king named ‘Ad, who ruled over a region whose capital was “Wūbar”. From this person you have the name of the tribe. So the term “أَخَا عَادٍ” can be translated as either the “brother of ‘Ād” or the “descendent of ‘Ād.” Obviously this expression does not mean that Hud was the immediate brother of ‘Ād, but the descendant of ‘Ād.
[46:21] Recall that the brother of ‘Ãd warned his people at the dunes—numerous warnings were also delivered before him and after him: “You shall not worship except GOD. I fear for you the retribution of a great day.”
وَاذْكُرْ أَخَا عَادٍ إِذْ أَنْذَرَ قَوْمَهُ بِالْأَحْقَافِ وَقَدْ خَلَتِ النُّذُرُ مِنْ بَيْنِ يَدَيْهِ وَمِنْ خَلْفِهِ أَلَّا تَعْبُدُوا إِلَّا اللَّهَ إِنِّي أَخَافُ عَلَيْكُمْ عَذَابَ يَوْمٍ عَظِيمٍ
In addition, we see that the expression أُخْتَهَا which could be translated as “its sister” is used in reference to an “ancestral group” in 7:38.
[7:38] He will say, “Enter with the previous communities of jinns and humans into Hell.” Every time a group enters, they will curse their ancestral group. Once they are all in it, the latest one will say of the previous one, “Our Lord, these are the ones who misled us. Give them double the retribution of Hell.” He will say, “Each receives double, but you do not know.”
قَالَ ادْخُلُوا فِي أُمَمٍ قَدْ خَلَتْ مِنْ قَبْلِكُمْ مِنَ الْجِنِّ وَالْإِنْسِ فِي النَّارِ كُلَّمَا دَخَلَتْ أُمَّةٌ لَعَنَتْ أُخْتَهَا حَتَّىٰ إِذَا ادَّارَكُوا فِيهَا جَمِيعًا قَالَتْ أُخْرَاهُمْ لِأُولَاهُمْ رَبَّنَا هَٰؤُلَاءِ أَضَلُّونَا فَآتِهِمْ عَذَابًا ضِعْفًا مِنَ النَّارِ قَالَ لِكُلٍّ ضِعْفٌ وَلَٰكِنْ لَا تَعْلَمُونَ
The understanding that 19:27 is in reference to Mary, the mother of Jesus, being the descendant of Aaron also corresponds with the fact that Mary is never indicated to live in the same time period or location as Aaron and Moses. Their histories are separate in the Quran, so this verse only informs us that Mary was the descendant of Aaron, and not that Mary was the sister of Aaron.
What proof do we have that Mary was a descendant of Aaron?
From the Bible and the Quran we can determine that Mary was part of the priest class as she was offered to God to be brought up under the guardianship of Zachariah.
[3:36] When she gave birth to her, she said, “My Lord, I have given birth to a girl”—GOD was fully aware of what she bore—”The male is not the same as the female. I have named her Mary and I invoke Your protection for her and her descendants from the rejected devil.”
فَلَمَّا وَضَعَتْهَا قَالَتْ رَبِّ إِنِّي وَضَعْتُهَا أُنْثَىٰ وَاللَّهُ أَعْلَمُ بِمَا وَضَعَتْ وَلَيْسَ الذَّكَرُ كَالْأُنْثَىٰ وَإِنِّي سَمَّيْتُهَا مَرْيَمَ وَإِنِّي أُعِيذُهَا بِكَ وَذُرِّيَّتَهَا مِنَ الشَّيْطَانِ الرَّجِيمِ
[3:37] Her Lord accepted her a gracious acceptance, and brought her up a gracious upbringing, under the guardianship of Zachariah. Whenever Zachariah entered her sanctuary he found provisions with her. He would ask, “Mary, where did you get this from?” She would say, “It is from GOD. GOD provides for whomever He chooses, without limits.”
فَتَقَبَّلَهَا رَبُّهَا بِقَبُولٍ حَسَنٍ وَأَنْبَتَهَا نَبَاتًا حَسَنًا وَكَفَّلَهَا زَكَرِيَّا كُلَّمَا دَخَلَ عَلَيْهَا زَكَرِيَّا الْمِحْرَابَ وَجَدَ عِنْدَهَا رِزْقًا قَالَ يَامَرْيَمُ أَنَّىٰ لَكِ هَٰذَا قَالَتْ هُوَ مِنْ عِنْدِ اللَّهِ إِنَّ اللَّهَ يَرْزُقُ مَنْ يَشَاءُ بِغَيْرِ حِسَابٍ
The priest class in Jewish History were the descendants of Levi, and in Exodus 28 it indicates that Aaron’s lineage would continue this role. Additionally. The Gospel of Luke records that Zachariah and Elizabeth, the cousin of Mary, and therefore their son John the Baptist were all descendants of Aaron. From this it could imply that Mary could also be a descendant of Aaron.
As the Quran comes to confirm and supersede the Bible, we now know for sure that Mary was a descendant of Aaron.
The Gospel of Jesus: Guidance and Light
[5:46] Subsequent to them, we sent Jesus, the son of Mary, confirming the previous scripture, the Torah. We gave him the Gospel, containing guidance and light, and confirming the previous scriptures, the Torah, and augmenting its guidance and light, and to enlighten the righteous. [5:47] The people of the Gospel shall rule in accordance with GOD’s revelations therein. Those who do not rule in accordance with GOD’s revelations are the wicked.
Quran: The Ultimate Reference
[5:48] Then we revealed to you this scripture, truthfully, confirming previous scriptures, and superseding them. You shall rule among them in accordance with GOD’s revelations, and do not follow their wishes if they differ from the truth that came to you. For each of you, we have decreed laws and different rites. Had GOD willed, He could have made you one congregation. But He thus puts you to the test through the revelations He has given each of you. You shall compete in righteousness. To GOD is your final destiny—all of you—then He will inform you of everything you had disputed.
وَقَفَّيْنَا عَلَىٰ آثَارِهِمْ بِعِيسَى ابْنِ مَرْيَمَ مُصَدِّقًا لِمَا بَيْنَ يَدَيْهِ مِنَ التَّوْرَاةِ وَآتَيْنَاهُ الْإِنْجِيلَ فِيهِ هُدًى وَنُورٌ وَمُصَدِّقًا لِمَا بَيْنَ يَدَيْهِ مِنَ التَّوْرَاةِ وَهُدًى وَمَوْعِظَةً لِلْمُتَّقِينَ
وَلْيَحْكُمْ أَهْلُ الْإِنْجِيلِ بِمَا أَنْزَلَ اللَّهُ فِيهِ وَمَنْ لَمْ يَحْكُمْ بِمَا أَنْزَلَ اللَّهُ فَأُولَٰئِكَ هُمُ الْفَاسِقُونَ
وَأَنْزَلْنَا إِلَيْكَ الْكِتَابَ بِالْحَقِّ مُصَدِّقًا لِمَا بَيْنَ يَدَيْهِ مِنَ الْكِتَابِ وَمُهَيْمِنًا عَلَيْهِ فَاحْكُمْ بَيْنَهُمْ بِمَا أَنْزَلَ اللَّهُ وَلَا تَتَّبِعْ أَهْوَاءَهُمْ عَمَّا جَاءَكَ مِنَ الْحَقِّ لِكُلٍّ جَعَلْنَا مِنْكُمْ شِرْعَةً وَمِنْهَاجًا وَلَوْ شَاءَ اللَّهُ لَجَعَلَكُمْ أُمَّةً وَاحِدَةً وَلَٰكِنْ لِيَبْلُوَكُمْ فِي مَا آتَاكُمْ فَاسْتَبِقُوا الْخَيْرَاتِ إِلَى اللَّهِ مَرْجِعُكُمْ جَمِيعًا فَيُنَبِّئُكُمْ بِمَا كُنْتُمْ فِيهِ تَخْتَلِفُونَ