Isaiah 59:1 "Behold the Lord's hand is not shortened that it cannot save.."
"The Lord's hand" is not shortened
The Outstretched Arm
In ancient times the outstretched arm was an emblem of authority while the shortness of the arm or hand spoke of authority that had been diminished and extended only to a certain point. It was said of king Artaxerxes that his empire was so far reaching that he was named "Artaxerxes Longimanus" which means long-handed, not because his hands were physically long, but because the vast extent of his empire reached to the farthest parts of the known world.
There are many sculptures that have been found with interesting symbols of power, many being throughout Egypt, and some with the monarchs arm and hand outstretched, with rays of the sun coming down on it, with hands at the end of every ray.
Though this particular passage was spoken in a time when Israel was being called to turn from their evil ways, the message is clear that the Lord, as the ever-present, all powerful, king of all creation, extends his hand to offer the free gift of salvation to all who will turn to him.
Jesus Reaching Out His Hand
Jesus used this physical expression of reaching out the hand many times showing that there is no limit to His authority, and He, as the true King, can grant forgiveness, and power over death.
To the Jewish leaders this was a blasphemous thing, using this physical expression and thus identifying Himself with the Almighty.
Bibliography on Ancient Customs
The Art of Ancient Egypt, Revised by Robins, 272 Pages, Pub. 2008