In the Bible, Israel refers to a person, a people, a nation, and a place.
Jacob/Israel had twelve sons, which eventually became the twelve tribes of Israel (Matthew 19:28), the people of Israel, and later the nation of Israel. In the Bible, they were called the Israelites; nowadays, they are called Israelis.
The land in which they eventually settled was also called Israel.
Key verse about Israel: God said to him, “Your name is Jacob, but you will no longer be called Jacob; your name will be Israel.” So he named him Israel (Genesis 35:10, NIV)
A lifelong student of the Bible, Peter DeHaan, PhD, wrote the 1,000-page website ABibleADay.com to encourage people to explore the Bible. His main blog and many books urge Christians to push past the status quo and reconsider how they practice their faith in every area of their lives.