There has been some discussion on who the author of Matthew is.  Some believe it truly is Matthew, while others want to keep the author anonymous.  Some even believe Matthew was written a good 200 years after Christ's death and resurrection...

If Matthew did not write Matthew at the time of Christ, then the firsthand accounts recorded would no longer seem valid.  I haven't researched it yet, but could anyone direct me to evidence that Matthew indeed did write the first Gospel?  I have a brother in Christ who is currently in a Bible class with a seemingly atheist professor, and is now having doubts about his beliefs...

I believe fully that once you are saved you are always saved.  But I have run into a problem with a good friend of mine, who is set in the ways of the Church of Christ, so he believes you can lose your salvation.  I haven't talked much about it to him, but I am 100 percent sure I can prove to him that you are not saved by works and sinning before you die without asking forgiveness will not get you into Hell.  The problem is, he still believes that once you are saved by faith in Christ Jesus, if you have been proven wrong otherwise by some other means, you can lose salvation.  So if you become saved, but later in life are faced with something that is good enough to convince you that Jesus did not die for our sins, you can lose salvation.  That's hard to argue with, even if you do disagree with it.  Is it possible to lose faith?  There are several verses saying that people will "abandon the faith."  What should I say to this guy to convince him that salvation cannot be lost?

To look at suicide and say it is unforgivable is incorrect.  No, we can't ask for forgiveness beforehand and expect to be clean, and unless you live through a suicide attempt you won't be able to ask afterward.  But let me explain my resoning.

Jesus Christ died for ALL sins.  Not just adultery or stealing.  Christ provided us with a way to heaven through him.  Your ticket to heaven is not based on how big or little your sins are.  The Bible says that we are saved by faith and not by works.  Works are a result of the relationship we have with Jesus.

Think about this:  Say I lie to my parents about where I am going some night.  I go out and am in a fatal car accident.  I had no time to repent for lying to my parents but do I still get to go to heaven?  I sinned and did not ask for forgiveness!  What do you think will happen to me?

Matthew 12:31-32 says:
And so I tell you, every sin and blasphemy will be forgiven men, but the blasphemy against the Spirit will not be forgiven. Anyone who speaks a word against the Son of Man will be forgiven, but anyone who speaks against the Holy Spirit will not be forgiven, either in this age or in the age to come.

Blasphemy is the only recorded "unpardonable sin."  All other sins are still sin - no matter how big or small - and aren't too big for our Lord and Savior.

All Christians sin.  Otherwise we wouldn't need a savior.  Some people struggle with words that come from their mouth while other people struggle with thoughts of suicide.  The only difference is that thoughts of suicide can have a more permanent affect on the life that God gave you.  Don't doubt God with life.  He created you and has a plan for you.  Our God is a God of hope - not of giving up!  Grow stronger in your relationship with Christ and you won't have problems trusting Him.  

I always make a decision on whether or not a sin is a sin by this:  Will it ruin my whitness?  I don't think there's a better way to make a judgement.  WWJD used to be the popular thing, and it's still valid in my opinion.  But I believe we are on earth for 2 (main) reasons.  1 - Worship god with all our lives (Mark 12:30) 2 - Help bring others to the saving knowledge of Jesus Christ (Matthew 28:19).  If we are doing things that hinder our worship or our ability to whitness to others, we aren't glorifying God.  Whether you call it sin or not, that's up to you.  God gave us all the ability to judge the difference in right and wrong.