How does the Bible explain spiritual death?

According to Genesis 2:17, God warned Adam that eating from the tree of knowledge would result in death. This death was not physical at that moment but was spiritual, leading to a separation from God. Paul later elaborates on this in Ephesians 2:1, stating that we are born dead in trespasses and sins. This state of spiritual death means that a person cannot perceive, understand, or choose God on their own because they lack spiritual life. Hence, the necessity of being born again emerges as the only means through which one can gain true spiritual life and the ability to respond to God.