Final answer:
Moses spoke through divine revelation, receiving messages and instructions directly from God. God spoke to Moses through a burning bush and the Ten Commandments were written by God on stone tablets.
Step-by-step explanation:
Moses spoke through a process called divine revelation, which means that he received messages and instructions directly from God. In the book of Exodus, it is mentioned that God spoke to Moses through a burning bush, where Moses was instructed to lead the Israelites out of Egypt. Additionally, when Moses received the Ten Commandments on Mount Sinai, it is said that the words were written by God himself on two stone tablets.