Gino - First..... ALL of God's word (scripture) is given by inspiration of God, and is profitable for doctrine, for reproof, for correction, for instruction in righteousness, that the man (or woman) of God may be complete, thoroughly equipped for every good work. (James 4:16)
 
A full understanding of ALL of God's Word gives us a more complete understanding of Who God is, His character, His attributes and what He requires of us. And... what the consequences are for disobeying our Lord and not meeting His requirements.

Leaders and teachers (assuming they know God) are held responsible for how they lead by example and by what they teach the people of God and say on His behalf.
 
The people are held responsible for knowing God, His Word, His voice and following only Him.
 
In certain areas and collectively people are judged by God and punished according to their beliefs held in common that do not meet His requirements, laws and statutes. (as in the letters from Jesus to the seven churches in Revelation 2,3)
 
Revelation 3:1-6
“I know all the things you (all) do, and that you have a reputation for being alive—but you are DEAD. Wake up! Strengthen what little remains, for even what is left is almost dead. I find that your actions....... do not meet the requirements of My God. Go back to what you heard and believed at first; hold to it firmly. REPENT and turn to Me again. If you do not (obey) wake up.....I will come to you suddenly, as unexpected as a thief. (You will not be ready)
 
“Yet there are.... SOME (not many)  in the church in Sardis who have not soiled their clothes with evil. They will "walk with Me" in white, for.......THEY (not ALL) are..... "worthy."
 
ALL who are... "victorious" will be clothed in white. I will never erase THEIR names from the Book of Life, but I will announce before my Father and his angels that they are mine.

“Anyone with ears to hear must listen to the Spirit and understand what He is saying to the churches.

2 Peter 3:14
Therefore, "beloved", since you are waiting for these, ( verse 11 - everything around us is going to be destroyed like this, what holy and godly lives you should live)  be diligent to be found by Him.... WITHOUT.... spot or blemish, and at peace.
 
2 John 1:8
"Watch yourselves", so that.... "you do not lose"... what we have worked for, that you... "may" be "fully rewarded."