Wow. First we need to remember that the New Testament was not written in English. The word "suffer" was chosen by translators to represent their best opinion of what the author was saying in the original language, Greek. This particular Greek word, as most do, has many nuances of meaning. The best meaning in all cases of translation must be determined from the context in which the word is used. The root of this word is "passion". Speaking of personal first hand experiance and the consequences that it produces physicly, emotionaly and psyclogicly.

This text is simply saying that Ananias was given a word from God to speak to Saul (later Paul) concerning the consequences of his conversion (Persicution from the Jewish religious authority, mocking and ridicule from the pagens and hostility from the Roman government). Jesus established the principle early on that each one must consider the cost of following Him before they begin (Luke14:27-28). Also and more to the point He stated that a true follower will endure the same rejection and hatred from the world that He did (Luke6:22-23, 40; John15:20). 

Faith in Christ brings great blessings, but often great suffering, too.  Paul would suffer for his faith (see 2 Corinthians 11:23-27).  God calls us to commitment, not to comfort. He promises to be with us through suffering and hardship, not to spare us from them.  
(I think this is where many people turn away from faith.  It may be that one feels, "If I believe in God, why isn't my life better?" ) 
Source:  Life  Application Study Bible NLV 

Probably because Saul would not believe Jesus was "GOD".

Because God (of you believe in him) is a vain, bloody-minded sadist. I'm glad I don't.

Dont believe everything you read.

Becouse He wil be a big instrument in the off god, and just an exemple for the world.

I've had more suffering and hardship sense I became a Christian than before, but each time I've come to know God better than before.

Maybe thats what Saul/Paul had to see before he could be a man of GOD.

I thought Saul became Paul or was it the other way round?