Here the word "hand" refers to power. The two phrases mean basically the same thing. The second clarifies that the brother whom Jacob intended was Esau. AT: "from the power of my brother, Esau" or "from my brother, Esau" (See: [[rc://en/ta/man/translate/figs-metonymy]] and [[rc://en/ta/man/translate/figs-parallelism]])
This is a quotation within a quotation. It can be stated an an indirect quotation. AT: "But you said that you would certainly prosper me, and that you would make my descendants ... number" (See: [[rc://en/ta/man/translate/figs-quotesinquotes]] and [[rc://en/ta/man/translate/figs-quotations]])
This speaks about the very large number of Jacob's descendants as if their number will be like the grains of sand on the seashore. (See: [[rc://en/ta/man/translate/figs-simile]])