The Saints were just as liable to have faulty natures as you or I, and Fr. Solanus was no exception. When he was young he was quick to get angry about little things, and it is said that he was somewhat rash and impulsive. All of the Saints were human, some of them moreso than others!
While God created each of us in His image, our personalities can differ greatly. Often this can cause dissension within the Church, with well-meaning Christians attacking one another. We need to remember to follow St. Paul's advice to the Thessalonians:
"Now we ask you, brothers and sisters, to acknowledge those who work hard among you, who care for you in the Lord and who admonish you. Hold them in the highest regard in love because of their work. Live in peace with each other. And we urge you, brothers and sisters, warn those who are idle and disruptive, encourage the disheartened, help the weak, be patient with everyone. Make sure that nobody pays back wrong for wrong, but always strive to do what is good for each other and for everyone else." (1Thess. 5:12-15)
Doesn't the world tear us down enough? Do we need to do that to one another, too? Instead, let's "encourage one another and build each other up" (1 Thess. 5:11) as St. Paul asks.
Fr. Solanus overcame his faults by his humble obedience to God, but he also used the awareness of them to make him patient with his brothers and sisters in Christ. Surely we are called to do the same...
Ven. Solanus Casey, pray for us!