COMMENTARY on 57:21
A. Yusuf Ali:

Translation:
Be you foremost (in seeking) Forgiveness from your Lord, and a Garden (of Bliss), the width whereof is as the width of heaven and earth, 5306 prepared for those who believe in Allah and His messengers: that is the Grace of Allah, which He bestows on whom 5307 he pleases: and Allah is the Lord of Grace abounding.
Commentary:

5306  Cf. 3:133, and n. 452.

5307  Bestows on whom He Pleases: that is, such grace and favour is beyond anyone's own merits. It is bestowed by Allah according to His Holy Will and Plan, which is just, merciful, and righteous.

 

Muhammad Asad:

Translation:
[Hence,] vie with one another in seeking to attain to your Sustainer’s forgiveness, 33 and [thus] to a paradise as vast as the heavens and the earth, which has been readied for those who have attained to faith in God and His Apostle: 34 such is the bounty of God which He grants unto whomever He wills - for God is limitless in His great bounty.
Commentary:
33  Sc., "rather than in striving for glory and worldly possessions": implying elliptically that no man is free from faults and transgressions, and hence everyone is in need of God’s forgiveness. (Cf. note 41 on 24:31.)
34  For a further qualification of the humility which characterizes true believers, see 3:133-135.