#Why did Paul write these things to the Corinthian saints while he was away from them?

Paul did this so that when he was with them, he would not have to act harshly toward them. [13:10]

#How did Paul want to use the authority the Lord gave him with regard to the Corinthian saints?

Paul wanted to use his authority to build up the Corinthian saints and not tear them down. [13:10]