Before the first Shabbos, where Hashem stopped creating things, the concluding overview sums up how Hashem related to His handiwork, finally complete:

וַיַּרְא אֱלֹהִים אֶת-כָּל-אֲשֶׁר עָשָׂה, וְהִנֵּה-טוֹב מְאֹד; וַיְהִי-עֶרֶב וַיְהִי-בֹקֶר, יוֹם הַשִּׁשִּׁי – And God saw all that He had done, and it was very good. With an evening and a morning, the sixth day. (1:31)

The Ramban teaches that everything in the universe, כָּל-אֲשֶׁר עָשָׂה including the less pleasant things in life, is brought together into what Hashem calls טוֹב מְאֹד – excellent. Ultimately – everything is for the best. With a greater perspective, everything turns out for the best.

The Netziv further adds that this was not just true of that moment – that unique point in existence where Hashem created things – from then on, all potential futures were dormant, awaiting their moment. Developing the Ramban’s concept, all latent potential is positive.

Rabeinu Bachye notes how at the conclusion of every other day, the Torah describes it as כי טוב – it was “good”. But on the final day, where all the different aspects of existence had been formed and came together, it became something else; טוֹב מְאֹד – “very” good. The creation itself was truly greater than sum of its parts; like a sophisticated machine, all the various levers, gears and cogs came together to become something utterly incredible.

The Kli Yakar points out the contrast between calling the first five days כי, and the conclusion of events is called וְהִנֵּה טוֹב מְאֹד. The Kli Yakar explains that כי is a term of clarification – that there is a deliberation weighing towards טוב with the other days. But when everything comes together, it is וְהִנֵּה טוֹב מְאֹד – it is clear and absolutely good.

The Sforno explains that the conclusion of creation achieved a balance, an equilibrium; existence was literally “at rest” – precisely the definition of Shabbos, which is itself the state of perfection. With the acceptance and absorption of the imperfections in the world, which the Torah calls טוֹב מְאֹד – then וַיְהִי-עֶרֶב וַיְהִי-בֹקֶר, יוֹם הַשִּׁשִּׁי – the sixth day – with the definite article, begins. Existence becomes whole, complete, and it is truly Shabbos. On such a sixth day – הַשִּׁשִּׁי – “the” perfect sixth day, Shabbos commences.

Indeed, the Torah continues;

וַיְכֻלּוּ הַשָּׁמַיִם וְהָאָרֶץ, וְכָל-צְבָאָם – And the heavens and earth were completed…

The incorporation of the negative into the positive is truly the epitome of perfection.