The Haftorah for Parashat Noach once again comes from the book of Isaiah (Isaiah 54:1-55:5), the Haftorah brings about many comparisons to the Parshah.
The Prophet states 'Broaden the place of your tent and the curtains of your dwellings stretch out, do not skimp, lengthen your cords and your tent pegs strengthen (Isaiah 54:2),' Just as the prophet is urging to broaden the tent, we see how in the Parshah, Noach had to miraculously fit in all the creatures and different species along with his family into an ark, which by nature would have been impossible to orderly fit everything in, however, as G-d created nature, he can alter nature as he made a miracle in fitting Noach and all that he was commanded to bring into the ark. Furthermore, one should always stretch out to others and broaden themselves in their personality to try and accommodate and be friendly to everyone, as we were all created in G-d's image.
A direct reference to Noach is highlighted in verse 9 (Isaiah 54:9), as the prophet states, 'For like the waters of Noach shall this be to me, as i have sworn never to pass the waters of Noach again over the earth.' The flood at the time destroyed the whole world and it needed to be reworked afterwards, however this is an assurance that this type of calamity would not occur again, however punishment may still come through a flood of some sort or via water, just as we see the wicked Egyptians at the Red sea drowned and other calamities have occurred in history, however the water has never again destroyed in totality.
The Prophet states how the Jewish children will be students of Hashem and abundant in peace (Isaiah 54:13). This was the complete opposite to how it was before the flood occurred, man was very wicked and their sins were abundant (Kiddushin 13).
G-d creates everything for reason, he brings about bounty into the world and also created destroying agents to ruin (Isaiah 54:16), which we saw evident in the Parshah how he used the ravaging waters to destroy nearly all of mankind.
The prophet proclaims 'Everyone who is thirsty, go to the water (Isaiah 55:1),' in fact many of the commentators have said that when the word 'water' is used it is also in reference to the Torah, The Gemara, explains this as spiritual thirst, all who seek it should drink of Torah's nutritious teachings (Baba Kama 82a). A verse composed by Shlomo Hamelech says, 'You are a garden fountain, a well of flowing water (Shir Hashirim 4:15),' Just as water is a source of life for the world, so too the Torah is a source of life for the world!
The Haftorah concludes relating about a covenant that G-d has sealed with the Jews (Isaiah 55:3). It is no coincidence that G-d brought about the 'rainbow' in this weeks reading as a sign that each time when it rains, he would not flood the world again (Bereishit 9:12-13)!