Important article by Sidney H. Griffith (who alludes a little to Luling work and nasara issue ) :
Late Antique Christology in Qurʾānic Perspective
You can find it here : Georges Tamer (2019) - Die Koranhermeneutik von Günter Lüling
Available:
https://bit.ly/2TjQDPrthanks to Maghraye.
Interesting as Griffith has worked since time about this topic.
1st edit : Reynolds in (in fact) on the same side as Griffith about the :
"A considerable controversy has arisen among recent historians of Islamic
origins about the Christian denominational identity of the “Nazarenes” (an-na-
ṣārā), the Qurʾānic term for “Christians”, of whom the Qurʾān speaks some fourteen
times. On the basis of what the Qurʾān has to say about Jesus the Messiah
and his mother, Mary, many researchers have taken the evidence of the relevant
passages as a warrant for postulating the existence in the Arabian ḥijāz in the
first third of the seventh century of groups known from earlier Christian heresiographical
texts, whose Christology most nearly approximates that of the Qurʾān,
whose views could then be considered as sources for the Arabic scripture. It is in
this way that a number of historians have taken the further step of postulating
the active presence in Arabia of various branches of Jewish Christians, principally the so-called “Ebionites”, “Elkasaites”, and “Nazarenes”, albeit that no other
shred of evidence for their survival in Arabia in the early seventh century has
come to hand. Having thus postulated their presence and actual influence on
the emerging Qurʾānic teaching, these scholars have not hesitated as a consequence
to cite them as present sources contributing to and even determining
the Christology of the Arabic scripture.⁴ By way of contrast, the present writer
has argued that the hermeneutically more plausible approach to discerning
the denominational and creedal identity of the Christians within the Qurʾān’s
purview, along with the Christology which the Qurʾān challenges, is to consider
the Qurʾān’s pertinent objections in reference to the views of the Christian communities
actually historically discoverable within its early seventh century milieu,
namely the so-called “Melkites”, “Jacobites”, and “Nestorians”, who,
along with the Manichees, flourished along the Arabian periphery and within
Arabia proper at the very moment of the Qurʾān’s origins.⁵"
Topic: Qur'anic studies today