The better question, or the Christian, is "What is Israel?"
Well since you moved the goal posts...
Genesis 12:1Nowthe LORD had said unto Abram, Get thee out of thy country, and from thykindred, and from thy father's house, unto a land that I will shew thee:
2And I willmake of thee a great nation, and I will bless thee, and make thy name great;and thou shalt be a blessing:
3And I willbless them that bless thee, and curse him that curseth thee: and in thee shallall families of the earth be blessed.
Genesis32:28 And he said, Thy name shall be called no more Jacob, but Israel: for as a prince hast thou power with God and with men, and hast prevailed.
Exodus 3:15 And God said moreover unto Moses, Thus shalt thou say unto the children of Israel, The LORD God of your fathers, the God of Abraham, the God of Isaac, and the God of Jacob, hath sent me unto you: this is my name for ever, and this is my memorial unto all generations.
16Go, and gather the elders of Israel together, and say unto them, The LORD God of your fathers, the God of Abraham, of Isaac, and of Jacob, appeared unto me, saying, I have surely visited you, and seen that which is done to you in Egypt:
Israel is the decendants of Jacob/Israel individually or corprately, free or slave and wherever they may be.