Beis Hillel says that the earth was created first and only after was the heavens created. The Tzlach has an elaborate explanation as to why the earth which is seemingly less important, was created first. The Tzlach explains (second approach) that the heavens is always run according to the laws of nature and never has supernatural events that testify to the fact that there is a creator controlling the universe. But on earth there are miracles and supernatural events such as in mitzrayim where the earth deviates from the laws of nature to prove that there is G-d in control. Shamayim is run through midas hadin = "elokim". Therefore, the numerical value of "ha'teva" (nature) = Elokim (i was always troubled by this one since i don't think that we find in tanach the term tevah referring to laws of nature - i recall discussing this earlier on this blog!). But the earth is sometimes run using midas harachamim that allows for a break in the laws of nature. The superiority of the earth that gave it the privellage to be created first is the fact that it sometimes breaks from the laws of nature to prove the existence and involvement of G-d.
Based on this the Tzlach explains the pesukim by the plague of kinim (lice). The magicians of Pharoh could not produce lice and they admitted "etzbah elokim hi" - the finger of Elokim. Yet they immediately continue to reject Hashem. Why? Tzlach explains that the claim of "etzbah Elokim" is a denial of G-d. They were claiming that it was a natural occurrence rather than a miracle. That is why the response was to send the plague of arov (wild animals) which was to show "ki ani Hashem b'kerev ha'aretz". Hashem = A G-d in control of the universe.