As-Saaffaat 37:128

(When he said to his people: "Will you not have Taqwa") means, `do you not fear Allah when you worship others instead of Him'

(Will you call upon Ba`l and forsake the Best of creators,) Ibn `Abbas, may Allah be pleased with him, Mujahid, `Ikrimah, Qatadah and As-Suddi said that the word Ba`l means lord. `Ikrimah and Qatadah said, "This is the language of the people of Yemen." According to another report from Qatadah, it is the language of Azd Shanu'ah. `Abdur-Rahman bin Zayd bin Aslam narrated from his father that it is the name of an idol which was worshipped by the people of a city called Ba`labak (Baalbek) which is to the west of Damascus. Ad-Dahhak said, "It is an idol which they used to worship."

(Will you call upon Ba`l) means, `will you worship an idol,'

(and forsake the Best of creators, Allah, your Lord and the Lord of your forefathers) means, `He is the One Who is deserving of your worship alone, with no partners or associates.'

(But they denied him, so they will certainly be brought forth,) means, for the punishment on the Day of Reckoning.

(Save the chosen servants of Allah.) means, those who believe in Him alone.

(And We left for him among the later generations.) means, he is praised and spoken of highly.

(Salam (peace!) be upon Ilyasin!) Similarly, one might say for Isma`il, Isma`in. This is the language (dialect) of Bani Asad; they say Mikal, Mika'il, and Mika'in. They say Ibrahim and Ibraham; Isra'il, Isra'in; Tur Sina', Tur Sinin. All of that is fine.

(Verily, thus do We reward the doers of good. Verily, he was one of Our believing servants.) We have already discussed the meaning of this above. And Allah knows best.

In verse 128, it was said: إِلَّا عِبَادَ اللَّـهِ الْمُخْلَصِينَ (except the chosen servants of Allah). Here, the word used is: مُخْلَصِينَ (mukhlasin) (pronounced with a fathah on the letter lam) which means chosen, elected, people Divinely identified as special. As such, these will be people whom Allah has elected to become recipients of the honor of having obeyed Him perfectly and made themselves deserving of the best returns and rewards from Him. Hence, it would be more appropriate to translate it in the sense of 'the chosen' rather than 'sincere.'