So Allāh rewarded them for what they said1 with gardens [in Paradise] beneath which rivers flow, wherein they abide eternally. And that is the reward of doers of good.
Translation: Saheeh International (English)
1 i.e., their admission and acceptance of the truth and commitment to Allāh's religion (Islām).
Allah rewarded them for their faith and their acceptance of the truth with gardens that have palaces and trees overlooking flowing streams, where they will live eternally. That is the reward of those who do good by following the truth and submitting to it, without any restriction or condition.