Jeffery1938, 194-5: »Obviously it may be taken as a genuine Ar formation from
ṣadaqa on the measure
fiʕʕīl, though this form is not very common. — As used in the Qurʔān, however, it seems to have a technical sense, being used in the sg. only of Biblical characters, and in the pl. as ‘the righteous’, and for this reason it has been thought that we can detect the influence of the Hbr-Aram
ṣaddīq. Thus Fleischer,
Kleinere Schriften, ii, 594, says: “Das Wort ist dem Hbr-Aram
ṣaddîq entlehnt, mit Verwandlung des Vocals der ersten Silbe in
i nach dem bekannten reinarabischen اتباع.” – In the OT [Hbr]
ṣaddîq means ‘just, righteous’, and is generally rendered by [Grk]
díkaios in the LXX. In the Rabbinic
ṣaddîqâ the sense of ‘piety’ becomes even more prominent and it is used in a technical sense for ‘the pious’, as in
Succa, 45, b. It is precisely in this sense that Joseph, Abraham, and Idris are called
ṣiddīq and the Virgin Mary
ṣiddīqaẗ in the Qurʔān, and there can be little doubt that both the Ar and the Eth [Gz]
ṣādəq are of this Aram origin.«
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