Hawzah News Agency – Prophet Moses peace be upon him says:

يا رَبِّ، مَن أهلُكَ الذينَ تُظِلُّهُم في ظِلِّ عَرشِكَ يَومَ لا ظِلَّ إلّا ظِلُّكَ؟ قالَ: فَأوحَى اللَّهُ إلَيهِ :الطاهِرَةُ قُلوبُهُم.

'O Lord, who are those whom You will shade under the Shade of Your Throne on the Day when no shade will avail other than Yourr Shade?' He said, 'Allah Almighty revealed, 'Those with pure hearts.'

Source: al-Mahasin, v. 1, p. 457, no. 1058