Translation:

28. He knows what is before them and what is behind them and they offer no intercession except for those who are acceptable and they stand in awe and reverence of His (glory).

Notes (Tafseer)

2688. Cf. xx. 109. Those who have conformed to the Will of Allah and obeyed His Law, thus winning the stamp of His approval.

2689. They: the usual interpretation refers the pronoun to the servants of Allah who intercede: it may also refer to those on whose behalf intercession is made: they do not take it as a matter of course, but stand in due awe and reverence of Allah's great glory and mercy.