Symbolism, Imagery, Allegory
The night before his assassination, Martin Luther King, Jr. delivered his last sermon in Memphis. He closed the sermon by saying, "I've been to the mountaintop. […] And I've seen the promised land" (source).
King is referencing Deuteronomy 32:49, where God shows Moses a panoramic view of the promised land of Canaan. But the concept of the promised land has its origin way back in the book of Genesis.
Big Promises
In Genesis, God makes his first Big Promise that Abraham's offspring will possess a pretty sizeable playground. He repeats the promise ad nauseum, but here's the very first one (Genesis is all about firsts, after all):
And Abram took Sarai his wife and Lot his nephew, and all their possessions which they had accumulated, and the persons which they had acquired in Haran, and they set out for the land of Canaan; thus they came to the land of Canaan. And Abram passed through the land as far as the site of Shechem, to the oak of Moreh. Now the Canaanite was then in the land. And the Lord appeared to Abram and said, 'To your descendants I will give this land.' So he built an altar there to the Lord who had appeared to him." (12:5-7 NRSV)
(Want to read God's other promises of land to Abraham? Check out: 13:14-15; 15:7; and 17:8. We told you they're everywhere.)
Most kids and grandkids inherit their parents' looks and hair-color or share similar personalities or annoying quirks. But Abraham's offspring—Isaac, then Jacob—inherit God's promise of the land of Canaan. That's right, God also appears to both of them to let them know that Canaan will be all theirs (26:2-3; 28:13; 35:12; 46:3-4).
Promise Deferred
But here's the catch. The promise is never fulfilled in Genesis.
What?!
Yep. After eight-ish iterations of the promise, it never comes true. When Genesis ends, Abraham's offspring are actually in Egypt. Abraham's descendants don't start taking possession of the land until later in the Bible, namely in the book of Joshua, which is four humongous books after Genesis.
But this deferral of the promise seems to be part of the point in Genesis itself, which thrives on the tensions between harsh human realities and big divine promises. For example, as soon as God promises the land to Abraham, there's a famine, which forces Abraham to go to Egypt for a while (12:10). It's kind of a bait and switch, don't you think?
Martin Luther King, Jr. uses the image of the promised land with a certain awareness that the promise of civil rights for which he fought was by no means a reality. He continues, "I may not get there with you. But I want you to know tonight that we, as a people, will get to the promised land" (source). King thought deeply about his Genesis. He knew that the promised land was a symbol that evoked a sense of hard-won hope in the face of sinister realities.
P.S. The concept of the promised land has caused everything from tension to all-out-war in the modern world. Check out "Current Hot-Button Issues and Cultural Debates" for all the deets.