Answer:
It was monotheistic.
Step-by-step explanation:
Monotheistic involves the belief that there is only one God. This is the general principle and philosophy of the religion of Judaism, Christianity and Islam. This is different from other religions which practice polytheistic religion which is the belief that there are many gods.
Christianity and Islam came after Judaism but the religions which existed before Judaism includes Zoroastrianism and Buddhism. The religions were both polytheistic.