But I laugh, And eat well, And grow strong. (lines 5-7)
This quote isn't so much about freedom from slavery as it is about the power of free will. Enslaved humans might not have power to do a lot of things, but they still have control over their attitude and minds, and in this poem the speaker uses that for all its worth. Instead of resigning himself to a life of slavery, he makes the best of what he has at that moment, finds humor in things, and works to make himself a stronger and better person. There's a powerful message regarding individual freedom in this quote, and it's that no matter the circumstances, there's a part of every human that is capable of being happily, forcefully free.
Tomorrow, I'll be at the table When company comes. (lines 8-10)
To be "at the table," in this poem, is quite literally to be free and equal. Instead of being ordered away to "eat in the kitchen," like he was a couple of lines earlier, to be free means to be allowed to do what any normal member of a society would do, in any situation. He can no longer be pushed away, out of sight.
Nobody'll dare Say to me, "Eat in the kitchen," Then. (lines 11-14)
Freedom is also about being free from worry – worry that you'll be abused, worry that you will be disrespected, worry that you will be treated unfairly. Here, the speaker frames freedom in such a way that not only will he not have to worry about such things, but that he'll command respect from the other people around him. You wouldn't dare order your friends around, now would you? You respect their rights as free human beings. That's exactly what's happening here.
They'll see how beautiful I am And be ashamed – (lines 16-17)
"Be ashamed of what?" you might ask. The obvious answer is, of course, "be ashamed that they ever enslaved African Americans in the first place." By asserting his race's right to all of the normal considerations that free people have in America, he is defining freedom as a kind of moral default position – all people are free and all people are beautiful, and to treat them otherwise is shameful.
I, too, am America. (line 18)
A lot of people associate the word "America" with the word "freedom." America is the "land of the free and the home of the brave," right? So when the speaker says that he, too, is America, he's basically stating that he, too, deserves freedom.