Authority and authoritarianism, despite the similarity in word structure, have quite different meanings. Authority concerns the exercise of power over others and this power can be executed well or badly. Bad exercise of authority can lead either to authoritarianism, always a bad thing, or at the other extreme, the under-use of the authority a person legitimately possesses. Some differences between ‘authority’ and ‘authoritarianism’ follow:
Authority can be good or bad, depending on how the person in authority uses his or her power.
Authoritarianism is always despicable.
Authority can involve an outworking of strength – intellectual, spiritual, emotional.
Authoritarianism is an outworking of weakness – intellectual, spiritual, emotional.
Authority can lead to a display of good character.
Authoritarianism is a display of bad character.
Authority can be directed towards those of equal strength.
Authoritarianism is aimed at the vulnerable, those at the mercy of the authoritarian, demonstrating the cowardly and hideous nature of authoritarianism.
The good exercise of authority builds up others.
Authoritarianism only ever rips down others.
Authority that is good manifests itself as care for those under it.
Authoritarianism seeks to harrass and harm.
The good exercise of authority yields wilfull submission in those under authority.
Authoritarianism yields great anger and resentment in those on its receiving end.

Those in authority include everyone from parents to politicians, business leaders to pastors and anyone involved in leading or governing others. The good exercise of authority is encouraged by Scripture while authoritarianism is denounced. You can find Paul writing about good parenting to the Ephesians and Colossians.
Ephesians 6:4 (NASB)
4 Fathers, do not provoke your children to anger, but bring them up in the discipline and instruction of the Lord.
Colossians 3:21 (NASB)
21 Fathers, do not exasperate your children, so that they will not lose heart.
The Old Testament has an important verse in Proverbs for parents but it needs to be understood carefully.
Proverbs 22:6 (NASB)
6 Train up a child in the way he should go,
Even when he is old he will not depart from it
Note the verses that precede this one:
Proverbs 22:4-5 (NASB)
4 The reward of humility and the fear of the LORD
Are riches, honor and life.
5 Thorns and snares are in the way of the perverse;
He who guards himself will be far from them.
As verse 6 on parenting follows these two verses, we can ascertain, without too much of a stretch, that we need to be watching our own conduct and attitudes first and that only then are we in a position to lead others including our own children. Sometimes, though, there are blockages in the life of a parent so that their God-given authority turns into ugly authoritarianism. This same ugly process can occur in anyone in authority.
Personal difficulties can so afflict some parents that they would do well to set about beginning a process of freeing themselves from their oppressions and anger. This can probably best be done through several mechanisms at once but a determination to be a good parent must be the impetus for embarking on change. My advice to anyone, particularly any parent under such oppression, is that they should first recognise that they have a problem. Seek help through counselling. Seek prayer. Seek to change. Otherwise, through being an authoritarian, you will end up producing one more angry person in the world. Don’t end up hating parents if they are behind your drive to be an authoritarian but understand that the cycle may have repeated over generations. Determine to be a circuit-breaker.
Good parenting has no room for harrassing a child or speaking to a child with disdain or contempt or disrespect. For Christian parents, it is about the example of a godly attitide in everyday matters. Children will learn most by demonstration of the faith in you through daily living with integrity and reliance upon God, thus applying Scripture to everyday life. Bringing up children in “the discipline and instruction of the Lord” involves first ensuring that the wielder of so-called authority put himself or herself under the authority of the Lord. In other words, there is no room for hypocrisy in any area of life and this includes in child nurture and instruction. Hostility and anger are bred in a child at the receiving end of authoritarianism. This anger can be later manifest in a myriad of unhealthy ways.
2 Timothy 3:16-17 (NASB)
16 All Scripture is inspired by God and profitable for teaching, for reproof, for correction, for training in righteousness; 17 so that the man of God may be adequate, equipped for every good work.
By truly following Scripture, the pitfalls of authoritarianism can be left dead behind you. Seek the good of those in your power. Self-reflect. Seek help. Seek prayer to change from being an authoritarian parent to one who holds true authority in a just, kind and wise way.