Finally, the prophecy in verse 13 undoubtedly gave Isaiah some hope that the House of Israel would not be lost forever: "But yet there shall be a tenth, and they shall return." So, here is the hope. There will be a tithing, one tenth, or a remnant who will return to Jerusalem at a future time. The prophecy continues, stating that when the remnant return, it "shall be eaten, as a teil-tree, and as an oak whose substance is in them when they cast their leaves; the holy seed shall be the substance thereof."
There is much symbolism in this passage. Even though during winter time a tree without its leaves may appear to be dead, there is still life in it. Similarly, even though it may appear like the House of Israel is desolate and dead, without further seed or progeny, there will be a remnant that will return and bring life back to the land and its people. From this remnant will come a "seed" or the promised Messiah, who will bring life back all-together (to all people). I think this Isaiah passage was perhaps alluding to Psalm 22, which is one of David’s Messianic Psalms.