Once, when he was only five or six years old, he accompanied his father, Bhaktivinoda Thakura, on a visit to one sadhu by the name of Svarupa Das Babaji, in Puri. When they met, this babaji told Bhaktivinoda, "You have no neck beads and no tilak. You are not a Vaishnava. You don't even have any Vaishnava dress." Bimala Prasada (as the young Sarasvati Thakura was then called) replied, "My father is an ajanma Vaishnava (a born Vaishnava) even without the outward signs." Upon hearing this, that babaji was so impressed with this young boy, who at such a tender age had explained such a highly philosophical point.
At birth, the umbilical cord had wrapped itself around his body like a brahmana leaving a mark which remained clearly visible throughout his life.
At the time of initiation, Gaura Kishora Das Babaji didn't change Sarasvati Thakura's name. Earlier in his life he had written a book called "Siddhanta Chandrika" a book on astrology. He received the name "Siddhanta” from a society of astrologers, in recognition of his contribution in the field of astrology; later adding the prefix "Bhakti" himself when he took sannyasa.
He would also use horses and elephants on occasion, so sometimes people would criticize, saying, "What kind of sadhu are you with all these nice clothes, horses and elephants?" but he exclaimed, "All horses and elephants should be used by sadhus only, not by anyone else. All cars are also for sadhus. Luxurious items in the world are required for Krishna's service and not anyone else’s."
Shortly after the disappearance of Gaura Kishora Das Babaji from this world, which occurred in Navadvipa, Sarasvati Thakura went ahead with plans to place him in a samadhi (tomb). However, due to pressure from the people of Navadvipa, and from one wealthy man in particular, Sarasvati Thakura had to place him in a samadhi, not in Mayapur, which was his desire, but on that rich man's land in Navadvipa. That rich man was particularly adamant about this. Sarasvati Thakura was then heard to proclaim, "Within one month this man will be finished!" and it was noted, in time, how this came to be a fact. Within one month all his businesses were finished. That man then came pleading to Sarasvati Thakura, exclaiming, "Please, you help me now. See my position. I made some mistake!" Sarasvati Thakura then replied, "What can I do? It is already done."
Whenever young men joined the Math, leaving their homes, their parents would sometimes come looking for them in order to take them back. Sarasvati Thakura would hide them under his bed and tell the parents that he did not know the whereabouts of their sons. All the other devotees would also reply in this way and the parents would then leave. Then Sarasvati Thakura would tell the boy, "Maya is trying to pull you to hell. That is maya crying, not your father and mother!"
Whenever anyone came before Sarasvati Thakura, even before they had time to offer their namaskaras, he would say, "Daso 'smi I am a servant." People often tried to touch his feet, but he would stretch out his long arms and say, "Daso 'smi," and prevent them, including his initiated disciples.
Srila Prabhupada, January 15, 1977, Conversation:
"Our guru maharaja was so strict. A little discrepancy he would chastise like anything; but we liked it very much."
Once, in Mayapur, a brahmachari was sleeping during Sarasvati Thakura's class, so he ordered him thrown in the Radha kund, saying, "I have invited my spiritual master here, but if he sees you sleeping he will go away."
Once, a very prominent, rich man came to the Gaudiya Math, and while taking prasadam asked again and again for rasagullas. Sarasvati Thakura asked him, "Are you eating prasadam or is the prasadam eating you? You should not eat prasada, as prasada is the bhokta (enjoyer). You are the bhogya (enjoyed). Don't try to eat prasada; it is not a material thing." This is similar to the advice he often gave, saying, "Don't try to see Jagannath. Jagannath is the Seer so let Him see you."
Once, it came to Sarasvati Thakura's notice that two sannyasis, Bhakta Gavasti Nemi Maharaja and Bhaktivivek Bharati Maharaja had said; "We are collecting the money. Unless we help guru maharaja he cannot preach. He is depending on us." Sarasvati Thakura told all the devotees during the next morning lecture: "You all stay inside the Math for the next fifteen days and chant Hare Krishna, without going outside to collect anything. I will maintain you all by the mercy of Krishna, and Vishnupriya, as well as Lakshmidevi, will bring so many things. Without your help, without your going outside, so many things will come to the Math." So for one day he went out personally on madhukari bhiksha (the traditional system by which sadhus begged alms door to door), forbidding all others to venture out. That day, so many things were brought, unrequested, to the Math: ghee, grains, vegetables, etc. Sarasvati Thakura had only gone out for one day, but for fifteen days, while everyone sat in the Math, so many things came. The devotees felt ashamed, but had learned an invaluable lesson.
When one Mayavadi sadhu was preaching his oneness philosophy in the presence of Srila Bhaktisiddhanta Sarasvati and his disciples while they were riding on a train from Calcutta to Puri, Bhaktisiddhanta ordered his brahmacharis to feed the sadhu some rotten mangos which had been donated to his party earlier (they were ripe when donated, but got rotten because Bhaktisiddhanta would not take them due to his vow, and therefore no disciple would take either). After being obliged to eat four mangos, that sadhu fell at Bhaktisiddhanta's feet and swore he'd never preach oneness again.
Once when Srila Bhaktisiddhanta Sarasvati was opening a new center in a house that had been given for the use of the Gaudiya Mission, a ghostly incident occurred.
He was staying in a room on the second floor. One brahmachari was in attendance, reading Srimad Bhagavatam while he worked at his desk. That brahmachari suddenly saw a bony-hand float in through the window. He cried out and fainted. When Srila Bhaktisiddhanta inquired the cause for his alarm, the brahmachari told what he'd seen, but Bhaktisiddhanta Saraswati didn't seem to take it as very important. He told the brahmachari to chant Hare Krishna and not to cry unintelligibly.
Thereafter the hand again appeared and floated into the room as if to grasp the neck of Bhaktisiddhanta Saraswati. This time the brahmachari chanted Hare Krishna and then fainted. Srila Bhaktisiddhanta Sarasvati revived the brahmachari, saying, "Don't faint. Chant and read Srimad Bhagavatam." When the hand came again, the brahmachari did just that. Srila Bhaktisiddhanta saw the hand and chanted, "Haribol!", and the hand disappeared. He then said to the brahmachari, "No need to worry, that ghost is now delivered."
Srila Prabhupada said that Lord Chaitanya preached "extended Christianity" in a Chaitanya Bhagavata purport. In other words, whatever Jesus Christ taught, those ideas are there in Lord Chaitanya's philosophy, but much expanded upon. He accepted Jesus as a Saktyavesa avatara. He spoke of the amandodaya daya of Lord Chaitanya – the mercy by which doing good to some doesn't do any harm to others.
Commenting on "Do not take the name of the Lord in vain" – the teachings of Jesus – Srila Prabhupada said that "in vain" means anyabhilasa (Material desires. See Chaitanya Charitamrita, Madhya 24.330.), or cultivating another motive other than pure devotion.
"Give us our daily bread" was interpreted by Srila Prabhupada that "bread" means "food for the soul." In Paul's letter he said that we don't sacrifice any animal, but "sacrifice yourself and chant the names of God." Srila Prabhupada quoted this. This is giving the idea of the sankirtan movement. About Jesus Christ he said, “He was a Saktyavesa avatara. He didn't teach this eat, drink, and be merry business."