Bad attitudes damage our relationship with God and eventually lead to separation from God. This is perhaps the most critical aspect of negative or bad attitudes.
It is strange, but when we develop a bad attitude, we often become un-teachable. This un-teachable state affects our relationships with others and especially with God.
Jeremiah 22:21 I spoke to you in your [times of] prosperity, but you said, I will not listen! This has been your attitude from your youth; you have not obeyed My voice.
This is what brings division and ultimately separation from God.
Isaiah 59:2Your iniquities have made a separation between you and your God, and your sins have hidden His face from you, so that He will not hear.