Jesus began to speak first to his disciples, saying: "Be on your guard against the yeast of the Pharisees, which is hypocrisy." (Luke 12:1)Thus the topic of this statement relates to the teachings of the Pharisees, as explained with this previous verse.
But what do the Pharisees have to do with something concealed being brought into the open? And why does Jesus speak of "What you have said..."?
Jesus is speaking of knowledge and teaching. Jesus' disciples will be instructed by Jesus to pass his teachings on to others. Thus he is teaching them about the topic of passing on knowledge. First, he instructs them to not hear the teachings ("yeast") of the Pharisees. Then he speaks of knowledge and teaching:
"There is nothing concealed that will not be disclosed, or hidden that will not be made known."
Sometimes Jesus' teachings were a bit mysterious because he spoke in parables, and some of his disciples would get confused. Jesus explained this elsewhere:
The disciples came to him and asked, "Why do you speak to the people in parables?"
He replied, "Because the knowledge of the secrets of the kingdom of heaven has been given to you, but not to them. Whoever has will be given more, and they will have an abundance. Whoever does not have, even what they have will be taken from them. This is why I speak to them in parables: "Though seeing, they do not see; though hearing, they do not hear or understand." (Matt. 13:10-13)This was stated slightly differently in Luke:
His disciples asked him what this parable meant. He said, "The knowledge of the secrets of the kingdom of God has been given to you, but to others I speak in parables, so that, " 'though seeing, they may not see; though hearing, they may not understand.'" (Luke 8:9-10)
"What you have said in the dark will be heard in the daylight..."
It is not as if Jesus is wanting to keep the teachings of the Supreme Being private. Why then would he travel the countryside teaching?
Rather, what he was teaching was for a select few: Those who were ready to hear. Those who had a desire to come to know and love the Supreme Being.
Those who didn't have that desire would not understand the Truth even if they physically heard it: "though hearing, they may not understand."
"... and what you have whispered in the ear in the inner rooms will be proclaimed from the roofs."
This is the process the Supreme Being utilizes to broadcast His message to us. Externally, He utilizes His messengers to pass on His teachings - from Teacher to the student, and confirmed by scripture (which portrays the teachings of Teachers before).
Then the Supreme Being teaches from within as well. For a person who has respected and carefully heard the teachings of His messenger, the Supreme Being teaches from within as the Holy Spirit. This was confirmed specifically by Jesus:
"But the Advocate, the Holy Spirit, whom the Father will send in my name, will teach you all things and will remind you of everything I have said to you." (John 14:26)Here "send in my name" means that the Supreme Being recognizes the student's observance and dedication to God's representative.
Why, one may ask, would God need His representative to teach us externally before He teaches from within? Can't the Supreme Being just come and teach us from within only?
This question also relates to the many people over the centuries who have claimed to have had a vision of the Supreme Being or of Jesus from within and thus claim this vision gives them the ability to teach to others.
Yet such a position is actually hypocritical. A person who says they have received a vision from within and this gives them the right to teach to others is saying that they didn't need an external teacher, but others - those whom they are teaching to - do need an external teacher - more specifically, themselves.
This is also what has taken place within the various sectarian institutions - many of whom were founded by those who claimed to have some sort of internal vision and thus the right to teach others. Yet many of these didn't have or follow their own teacher and thus created their own interpretation of the teachings of Jesus and other prophets.
Yet again this is hypocritical, because why do we need them as our teacher? Why can't each of us just have our own vision? Why do they even need to teach if we each can just have a vision like they did?
Or are they saying that they are somehow special - and better than everyone else?
If they are teaching that we should follow them, then it would be hypocritical to also say we need to hear their teachings, when they didn't need to hear and follow the teachings of a teacher. To "follow" means to do what they do, right?
In fact, this is one of the main reasons why these ecclesiastical sectarian institutions have strayed so far from what Jesus really taught: Because their founders believed their so-called visions gave them the license to create their own philosophy and interpretation of Jesus' teachings.
Yet if they really followed Jesus' teachings then they would also seek and accept an external teacher, just as Jesus showed us with accepting John the Baptist as teacher - symbolized by his accepting baptism.
And they would also pass on the teachings of that teacher and those teachers of that teacher - just as Jesus did. The fact that Jesus specifically passed on the teachings of John was portrayed in these three verses:
In those days John the Baptist came, preaching in the Desert of Judea and saying, "Repent, for the kingdom of heaven is near." (Matt. 3:2)While this ("The kingdom of heaven is near") is a generalization of Jesus' teachings (find the meaning here) - we can see that Jesus passed on what John taught and then instructed his students to pass on the same teaching.
From that time on [after John's imprisonment] Jesus began to preach, "Repent, for the kingdom of heaven is near." (Matt. 4:17)
[Jesus told his disciples] "As you go, preach this message: 'The kingdom of heaven is near.'" (Matt. 10:7)
And while we might accept that Jesus was exalted and didn't need a teacher, Jesus himself said after John questioned whether he should baptize Jesus:
"Let it be so now; it is proper for us to do this to fulfill all righteousness." (Matt. 3:15)"All righteousness" refers to the process of becoming a student before becoming a teacher. One must become a student before becoming a teacher.
The reason behind this is to avoid the dangers of mental speculation. The physical mind has a great ability to deceive. It can make us believe we have had a special vision. The mind can deceive us into thinking that we can make up our own interpretation and that since we made it up it must be correct. The mind can deceive us into thinking that we have some special gift that others do not have, and thus the ability to teach to others despite not having been a student.
But if one sits at the feet of a teacher and learns from them those teachings that the teacher is passing on from his own teacher, the student will be able to discern the difference between what is coming from the mind and what is coming from the Supreme Being within. This is illustrated by Jesus' statement above:
"But the Advocate, the Holy Spirit, whom the Father will send in my name, will teach you all things and will remind you of everything I have said to you."
In other words, the Holy Spirit acts to confirm the teachings of His representative - to clarify them. But never to contradict them.
Why is this important? Because the spiritual realm (the kingdom of heaven) is about the loving relationships that exist between the Supreme Being and His loving servants. To learn from one of His loving servants means to enter into those loving relationships that exist between the Supreme Being and His loving servants.
This is why even Jesus' teachings did not contradict the teachings of John, or the Prophets. And even his most important instruction was quoted from Moses' teachings:
" 'Love the Lord your God with all your heart and with all your soul and with all your mind.' This is the first and greatest commandment." (Matt. 22:37-38 quoted from Deuteronomy 6:5)