We can only begin to understand Gods Word once we have been chosen. It does not even depend upon our acceptance of the call, because we can know the truth in our heart and yet deny it. However, it does depend upon our acceptance to be open to it. If we are unwilling to open our hearts to Gods Word then we will not have the ears to hear, as our Lord often said. It is that openness that invites the Holy Spirit to bring us understanding. At the same time we must remember that not all are at the same level of understanding (Rom 14), and we must be careful not to criticize or condemn, but simply lay our understanding out for others to see. We also must remember that we as anyone else can be deceived by what we may think to be the Spirits leading, when in reality it is our own desires to be right or justify sin in our lives. That is why it is very important to not only learn how to distinguish between Spirits (discerning) but to bring everything before the Lord in prayer. The Holy Spirit will lead us in our understanding weather we bring it to Him or not, though if not then it may take us longer to figure out we could be wrong about something and we could send many down a wrong path. But, our Lord knows this about us and is prepared for such. That is one reason He is patient with us, because like children we are learning. And, that is another fact we must always remember, we like everyone else do not know it all and can be wrong. Arrogance is the sin of pride weather we see it as such or not.
Finally no matter how bad we long for someone to get it, to know the truth of God and accept His love and sacrifice. Unless He has chosen them to understand the truth they will not. I know that can sound cruel, but God has known from before time who would accept Him and who would not. There are those whose heart has been hardened because of this, and it is not because of us they don't. It is just our commission to share Gods love and Gospel, not to save that is upon God. But, it is upon us to see that in even this, the grace God has shown us, not in pride but love, and compassion for those whose heart has already judged them. For if we judge those who will not accept Him we also judge ourselves. Just rejoice in our salvation and pray for those who have yet to know Him.