According to the Quran, two key characteristics of those who will inherit the earth to rule the world are: TAQWA (تقوی) and SALAHIYAT (صلاحیۃ)
اِنَّ الْاَرْضَ لِلّٰهِ يُوْرِثُهَا مَنْ يَّشَاۗءُ مِنْ عِبَادِهٖ ۭوَالْعَاقِبَةُ لِلْمُتَّقِيْنَ
Surely the earth belongs to Allah. He makes its inheritors whom He wills of His servants; And (His will is that) the ultimate succession (to authority in the earth) belongs to Muttaqeen (i.e. those who are conscientious and act with integrity and uprightness).
Al-Quran Surah 7: Verse 128
اَنَّ الْاَرْضَ يَرِثُهَا عِبَادِيَ الصّٰلِحُوْنَ
That the inheritors of the earth will be My servants who are Salihoon (i.e. those who are incorrupt, righteous and fit for the position)
Al-Quran Surah 21: Verse 105
With reference to the infinitive noun sulooh (صلوح) or salaah (صلاح), Salihoon means good, incorrupt, right, just, righteous, virtuous and honest people.
With reference to the infinitive noun salahiya (صلاحیۃ), the word Salihoon means the people who are suitable, appropriate and fit for a position.