it is they who are destined for paradise, therein to abide as a reward for all that they have done.

Such shall be Companions of the Gardens, dwelling therein (for aye): a recompense for their (good) deeds.

Such are rightful owners of the Garden, immortal therein, as a reward for what they used to do.

These are the owners of the Garden, abiding therein -- a reward for what they did.

Those are the companions of Paradise, abiding eternally therein as reward for what they used to do.