Q: What about Nichiren’s warnings to his disciples not to reveal his important doctrines, and in particular the Gohonzon? 
A: The Daishonin was very specific about this matter in his letter "On Repaying the Debts of Gratitude":
"One should never speak of matters pertaining to Buddhist doctrines to someone who has no faith, regardless whether the person is a close friend or relation or a stranger. This is something you should keep in mind. I have inscribed the Gohonzon for you.”
(Writings of Nichiren Daishonin, p. 737)
Security of the doctrine and protection of his disciples was his concern. The same Gosho explained that certain important doctrines should be kept secret at that time for their protection and for the security of disciples: 
"In the enclosed treaties I have written matters of utmost gravity. It would be wrong, therefore, to make the contents known to persons who do not understand the essence of Buddhism, and even if they are made known only to persons who do, if there are too many people involved, then word of the contents is likely to reach the ears of outsiders. That would not be conducive to your welfare, nor to mine."
The atmosphere of hostility and plots, at the time of the Daishonin’s advent, prompted him even to caution his close disciple Nanjo Tokomitsu to keep his beliefs secret  "... it is advisable that you do not carelessly let it be known that you are a believer." (Writings of Nichiren Daishonin, p. 800) 

In the Gosho “On the Treasure Tower,” Nichiren Daishonin instructed Abutsubo not to carelessly reveal the Gohonzon, which was specifically inscribed for him, and asked him to keep it only within his trusted circle: 

“Faith like yours is so extremely rare that I will inscribe the treasure tower especially for you. You must not transfer it to anyone but your son. You must never show it to others unless they have steadfast faith. This is the reason for my advent in this world.” 
In this sentence, the Daishonin refers to the Gohonzon as the reason for his advent in the world.

This work has been compiled by individual SGI members and is solely our personal opinion, based on years of practice and study.