Jewish answer:
The Hebrew Bible is important because it tells the history of the ancient Israelites, as well as giving us the teachings of such prophets as Moses, Isaiah and Jeremiah, the stories of kings like David and Saul, and the development of the ethics and beliefs of the Jewish religion. Our tradition is that the Hebrew Bible is from God (Exodus 24:12), given to us to provide knowledge, guidance, inspiration, awe and reverence, advice, law, comfort, history and more. It is the basis of Judaism.
The Hebrew Bible has also heavily influenced Western society.
All look to the Old Testament as the root of their beliefs
Abraham was the father of the Jewish nation, as well as Islam, he was always obedient to god.
The old testament is common for Jews and Christians and not Muslims. However, Torah that is part of the old testament is common to Muslims.
It's the same God (Allah) as in the Old testament.
Judaism, Islam and Christianity all worship the same, SINGULAR God. The writings of the Jewish Torah and the Christian Old Testament are revered in Islam.
The Old Testament.
Jesus said that he did not come to abolish the Old Testament laws, but to fulfill them. He emphasized the importance of following the spirit of the law rather than just the letter of the law.
Ways I would express it is thru out the whole bible god is the eye of the world old testament or new testament. We learn as they did in the old testament the same purpose of unification a desire to find our way and final we are and always will be the all with god from the beginning to the end.
Apart from Christianity, you could say that all other religions do not accept the New Testament. (The religion that accepts the Old Testament, or Hebrew Bible, but not the New Testament, is Judaism.) It is also worth noting that Islam rejects the New Testament as written, but does not reject the spiritual nature of the events it describes. Islam holds the New Testament to be a corrupted form of Jesus's Ministry, something that is very important in Islam.
Ahmad is not mentioned in the Old Testament or the New Testament. Ahmad is an Arabic name and became popular after the Rise of Islam. If perhaps the person was looking for Ahab, he appears in 1 Kings chapters 16-22 and 2 Chronicles chapter 18.
Judaism: Tanakh (Hebrew Bible) Christianity: Bible Islam: Holy Quran
Bibles, called "Red Letter Editions" feature the words of Jesus Christ in red. Jesus only appears in the New Testament, that is why there is no red in the Old Testament. Truly every word of the Holy Bible is inspired by God, and the lack of red in no way diminishes the importance of the Old Testament.