We do not know anything more about Alexander except that he was a metal worker and a spiritually dangerous man.  He was not a believer; indeed, he strongly opposed the gospel.  These verses imply that, in order to dissuade people from listening to Paul, he made trouble for the apostle, probably lying about his character or integrity and stirring up people’s hatred.
 
Paul was not angry.  He did not want to ‘get his own back’ on the man, but he left it to the Lord to punish Alexander for his rebellion.  He also warned Timothy not to be naïve, but to watch out for this spiritual troublemaker.  Having successfully caused trouble for the Apostle Paul, he was quite capable of raising a storm of protest against Timothy, in an attempt to discredit the Saviour and destroy the church.
 
We must not be naïve.  Enemies of Christ can be found everywhere and some of them take particular pleasure in ridiculing the church by discrediting Christian leaders.  Their final judgement rests only in God’s hands.  We cannot and must not attack them.  However, we must be wise in understanding their wicked desire and protecting the church by living out the truth of God’s Word, praying for God’s protection and warning believers not to be duped by their lies.

Unfortunately, in the name of niceness, many spiritually dangerous people are being tolerated.  Wise believers will not give such people the opportunity to infect the church even though they may deceive unbelievers.