Valmiki Ramayana Bala Kanda Sarga 24 Shloka 21

इन्द्र: Indra, यदा when, निर्मल: removed of his impurities, निष्करूशश्च unaffected by hunger, शुचि: अभवत् became pure, प्रभु: all powerful lord, सुप्रीत: highly pleased, देशस्य for that region, अनुत्तमम् excellent, वरम् boon, ददौ gave.

Cleansed of his impurities and his hunger gone, Indra once again became pure. Allpowerful Indra highly pleased gave an excellent boon to that region.