How do we know God's name signifies His eternality?

God's self-identification as 'I am that I am' in Exodus 3:14 showcases His eternal nature. This name implies that He has always existed and will always exist, transcending the confines of time. The letters in His name reflect not just a title but a profound reality of His self-existence. As noted in Psalm 90:2, 'from everlasting to everlasting, thou art God,' affirming the boundless nature of His being. This name, therefore, establishes God as the foundation of existence, untainted by creations or temporal change, further substantiating the belief in His perpetual presence and unchanging nature.