3137 This is a combination of three Abbreviated Letters, as to which, generally, see Appendix I, printed at the end of S. 2- This particular combination occurs here and at the head of S. 28, while the intervening Surah 27 has it in the syncopated form Ta ' Sin. None of the explanatory conjectures which 1 have seen carries conviction for me. If the letters stand for Tur Sinin ( Mount Sinai ) and Musa (Moses), whose story fills a large part of this Surah, why is the letter Mi m omitted in S. 27. where the same meaning would apply? There is, however, one fact to which I should like to draw attention. There are eleven sections in this Surah, and eight of them end with the word Rahim (with the final Mim). The three exceptions are sections 2 and 3, and section 11. But sections 2 and 3 are part of the story of Moses, which is completed in section 4, and that ends with "Rahim", The main argument in section 11 ends at verse 217, which ends with Rahim. We can say that the whole Surah is based on a refrain in the word "Rahim". Whether this has any bearing on our present enquiry I cannot say. My own position is that where we have material, we should pursue our researches, but we should never be dogmatic in such matters, as some Mysteries can never be solved by mere research.