Warn
Some people just didn't hear the warnings; others paid no attention to them. When they opened an e-mail with the subject heading  "I Love You," instead of a tender e-mail from a friend, they found a destructive computer virus. How foolish they were not to heed a warning that could have prevented so much mess and misery! Yet history is full of people who ignored warnings. Before each Biblical account of God's punishment of humankind's sinfulness, the Lord always sent a clear warning, giving people a chance to repent (see Repentance).

We shake our heads at those who reject God's warnings of hell, but we also need to take a good look at ourselves to see if we are still listening to his warnings - warnings that come through the Bible or through our Christian friends.

God warns people that if they do not turn from their wicked ways, harsh punishment awaits them.
2 Kings 17:13
Ezekiel 3:19-21
Luke 16:28
The Lord issues warnings to protect people from harm.
Exodus 19:21-24
Acts 20:23
One of the Bible's biggest warnings: Do not alter the words contained in the book of Revelation.
Revelation 22:18
We are to warn fellow Christians if they stray from following Jesus Christ or if they cause divisions in the church.
1 Thessalonians 5:14
2 Timothy 2:14
Titus 3:10