1 The god did grant his daughter's dear demand,

dear > earnest; expensive

2 To do his nephew in all riches flow;

do > make nephew > grandson

3 Eftsoons his heaped waves he did command

Eftsoons > Soon; thereupon

4 Out of their hollow bosom forth to throw 5 All the huge treasure, which the sea below 6 Had in its greedy gulf devoured deep,

gulf > abyss

7 And him enriched through the overthrow

him > itself (if referring to the sea); him (if referring to Nereus)