How our parents taught us about life is similar as to how God reveals His Words to men.
When we were toddlers, our parents told us to do things that we didn't understand. Sometimes they would even tell us to just follow. We even get scared with them when they do it. It's almost the same when God started talking to His people. There seemed to be a lot of confusions and some words humans can't fathom. They got scared of Him also. But most of the time, just like our parents, God asks us to do things we can't understand because they are trying to protect us from bad things we are not aware of. As little kids, we were bold and adventurous so as the earlier men before they started understanding the law of God and nature that we try to do a lot of stupid things that could hurt us.
Not until we grew older that we became aware of the dangers of heights, fire, water and sharp objects. We were curious when we were kids even when our parents told us not to play with them. Some of us abide. Some did not but then learned from the experience. Just like how the early men did not realize how vices, infidelity, promiscuity, over consumption of a lot of things could harm them physically, mentally and emotionally. Many of them followed what God told them. But others did not and learned the hard way.
Then came the time that our parents saw our maturity and started to explain things to us in depth. Just like how knowledge of science, philosophy, psychology and other advance learning started to bring light to God's wisdom. It became easier for the people to understand His words and actions.
We react differently to how our parents treated us same as to what God wants us to do or to be. Either we grow as faithful and loving children or as rebels. And there are those who are just like the prodigal son who comes back to his father after realizing his mistakes. Or maybe like some who hardened their hearts and forever leave their parents and families, forgetting everything. Then there are those who follow only the things they like which just meant it's not their parents whom they are listening to but themselves.
Our fathers and mothers aren't flawless. They can do things wrong and this might impact as to what kind of adults we become. Our parents are human too. But not God. God is perfect so as His words. As to how we can be sure if we're listening to Him right, we're asking the wrong question. Let us ask ourselves first if we truly believe Him. It's the prerequisite before we are even capable of sitting down and listening to Him.