Wordsworth laments modern man's separation from the natural world. He understands the rapid industrialization taking place in his time period as alienating humans from nature. He decries the worship of money and consumption, writing that "getting and spending, we lay waste our powers."

In the phrase "I'd rather be Pagan suckled in a creed outworn," he states that he would rather be brought up to believe in the Greek myths, even though he knows they are untrue, than to be so busy making and spending money that he loses his connection with nature. A pagan, he knows, may have a false set of beliefs, but at least those beliefs put him into harmony with the natural world, such as when a pagan can picture Proteus rising from the sea. What the poet definitely does not want is to be out of "tune" with the sea and the winds. He does not want to trade his heart, which is his love of nature, for money and things.  

Written in 1806 by William Wordsworth, in "The World Is Too Much With Us" the poet laments the imbalance that he perceives between his generation's present materialism and the natural world. The technological advances of his age have rendered the wind and waves impotent. Thus, at lines 9 and 10, the poet exclaims:

Great God! I'd rather be

A Pagan suckled in a creed outworn;

Given the lines that follow, with their references to Proteus (13) and Triton (14), it seems clear that Wordsworth is longing for a simpler time, a time in which the technology and advances of his age an age in which people prayed to divinities that ruled over nature. Thus, he uses references to these ancient Greek gods as an example of a pagan belief system. He calls such beliefs an outworn creed, because, in his society, no one believes in such gods anymore.

In sum, Wordsworth seems to be longing for a simpler time when the world had a more pastoral quality. Surely he doesn't really want to be a pagan, but he does appear to be yearning for a simpler time when people were not so materialistic and the joys of the countryside did not seem so far removed.