After providing cover for themselves in this way, they hear a familiar sound. The Hebrew form of the word walking
in this verse shows that this was not the first time the Lord had come to Adam and Eve in this way. He had come to man many times before in Paradise. It is also why Adam and Eve immediately recognize the sound and realize what is about to happen now.
This familiar sound now frightens them. It is a new and bad experience for them. Until now, there was reverent joy when the Lord came to them and instructed them, when Father sought his children in love. Now man himself has caused the situation to be such that he has to fear God; that he wants to flee from God and that God has become his enemy. Man no longer wants to be seen by God because God has become a threat to him. Fear has entered man’s life—even fear of the only living God.
8 And they heard the sound of the LORD God walking in the garden in the cool of the day, and the man and his wife hid themselves from the presence of the LORD God among the trees of the garden.