A short lecture based on the Gosho not Ikeda's opinions.

"In the sixteenth chapter, "Duration of the Life of the Buddha," the 

sutra also declares:  ‘As I said before, it is immeasurably long since 
I, Sakyamuni Buddha, obtained Buddhahood.  My life spans an 
innumerable and incalculably long period of time.  Nevertheless, I am 
always here and I shall never pass away.’" 

Kanjin Honzon-Sho, Nichiren Shu Overseas Propagation Promotion 
Association (NOPPA) page 36 

"Finally in the sixteenth chapter, the Buddha sometimes appears as a 
Buddha in the realm of Buddha but other times appears as some of the 
others who reside in the other nine realms.  This indicates that the 
ten realms are included in the realm of Buddha’s." 

Kanjin Honzon-Sho  (NOPPA) page 36 

This reference is included to refute the argument saying that 
Sakyamuni’s enlightenment occurred at a fixed point in the past by his 
reference to practicing the way of the bodhisattva. 

"Born to the human world, Prince Siddhartha, young Sakyamuni, became 
the Buddha.  These evidence should be enough to convince you to 
believe that the realm of Buddhas exists in the realm of men." 

Kanjin Honzon-Sho  (NOPPA) page 56 

"In fact Sakyamuni began to preach, planting the seed of Buddhahood in 
the eternal past... Sakyamuni Buddha continued to guide His disciples 
until they were all sure to attain Buddhahood during the preaching of 
the Lotus Sutra in His present life, completing the series of His 
preaching which began in the eternal past." 

Kanjin Honzon-Sho  (NOPPA) page 86 

"This means that Sakyamuni Buddha, Taho Buddha, and all the Buddhas in 
manifestation are in our minds, and that we, upholders of the Lotus 
Sutra, will follow in their steps and inherit all the merits of those 
Buddhas. 

"It means that Sakyamuni Buddha, within our minds, is an ancient 
Buddha without beginning, manifesting Himself in three bodies, and 
attaining Buddhahood in the eternal past  described as 500 
dust-particle kalpa ago. 

"In the same chapter, another passage reads: ‘The duration of My Life, 
which I obtained through the practice of the way of bodhisattvas, has 
not yet expired.  It is twice as long as the length of time stated 
above: 500 dust-particle kalpa.’  This reveals the bodhisattva-realm 
within our minds.  The bodhisattvas described in the fifteenth 
chapter, ‘Appearance of Bodhisattvas from Underground,’ who have 
sprung out of the great earth, as numerous as the number of 
dust-particles of 1,000 worlds, are followers of the Original Buddha 
Sakyamuni who resides within our minds." 

Kanjin Honzon-Sho  (NOPPA) page 94 

Here Nichiren explains the meaning of the oft mis-quoted reference to 
Sakyamuni’s practice of the bodhisattva way. 

"Now , when the Eternal Buddha was revealed in the essential section 
of the Lotus Sutra, this world of endurance (Saha-world) became the 
Eternal Pure Land, indestructible even by the three calamities of 
conflagration, flooding, and strong winds, which are said to destroy 
the world.  It transcends the four periods of cosmic change: the kalpa 
of construction, continuance, destruction and emptiness.   Sakyamuni 
Buddha, the Lord-preacher of this pure land, has never died in the 
past, nor will He be born in the future.  He exists forever throughout 
the past present and future.  All those who receive His guidance are 
one with this Eternal Buddha." 

Kanjin Honzon-Sho  (NOPPA) page 100 

"How lucky I am to be able to go to the Pure Land of Mt. Sacred Eagle 
and extinguish within one life my sin of slandering the true dharma 
ever since eternal past!  How glad I feel to be able to go to the Pure 
Land of Mt. Sacred Eagle and wait on Lord Sakyamuni Buddha, whom I 
have never seen yet!  May I guide first of all those rulers of this 
land who have persecuted me. May I tell Sakyamuni Buddha about my 
disciples who have assisted me. May I present this great merit to my 
parents, who gave birth to me, before I die." 

Kembutsu Mirai-Ki, NOPPA, page 262 

"I, Nichiren, of Awa Province graciously received the teaching of the 
Lotus Sutra from three masters (Sakyamuni, T’ien-t’ai, and Dengyo) and 
spread it in the Latter Age of the Decadent Dharma. 

Kembutsu Mirai-Ki, NOPPA, page 264 

After reading these excerpts, how can one support the idea that 
Nichiren is the Treasure of the Buddha?