Sri Guru-Purnima.

Appearance of Srila Vyasadev.

Disappearance of Srila Sanatana Goswami.

Beginning of Chaturmasya

Selected references to this day, on the Math's websites.

Audio. Vedavyas. Informal discourse by His Divine Grace Srila Bhakti Raksak Sridhar Dev-Goswami Maharaj.
"All the scholars in the world at present they admit that Vedavyas has distributed so many different thoughts. There is no one to compete with him in that matter... So many types of thoughts are represented by Vedavyas, in Mahabharat, Srimad Bhagavatam, so many Puranas, Vedas, Vedanta; all possible representations and considerations of all possible thoughts are represented by him alone. So he is master of all sorts of understandings. And he has given in his last days what is written in Bhagavatam: that love is all, Bhagavat Prem, Krishna Prem... 'The inner most hankering of every jiva soul is for this, for beauty and love, affection and harmony, not for power, not for knowledge or anything else.'"
11+ minutes, 2.5 MB mp3 audio

Audio: Sri Guru-Purnima day discourse. Amongst other topics, Srila Bhakti Sundar Govinda Dev-Goswami Maharaj describes a remarkable debate between Srila Guru Maharaj Srila Bhakti Raksak Sridhar Dev-Goswami Maharaj and a big pandit. That pandit was so impressed by Srila Guru Maharaj that he wanted his association at the time of passing from this world.
And:
"Today is Sanatan Goswami Prabhu's tirobhav (disappearance), and Vyasadev's avirbhav (appearance) happened on this purnima (full moon). And Nityananda Prabhu today did Vyasa-Puja in the house of Srivas Pandit, and ... Srivas Pandit organised this by order of Mahaprabhu."
Srila Gurudev speaking on Sri Guru-Purnima, 30 July 2007:
9 minutes, 4 MB mp3 audio

Audio: Chaturmasya begins. Srila Bhakti Sundar Govinda Dev-Goswami Maharaj speaks in 2005 about the rules of chaturmasya and our position as a practitioner. He affirms that vedic knowledge appears through Krishna and Vedavyas; and other great scholar personalities have notated it. He tells how Narad Muni instructed Vedavyas to feel in his heart through meditation and to write the pastimes of Lord Krishna for his full satisfaction; and how Jiva Goswami has shown us that when Mahaprabhu appeared everyone could understand what was the final advice of the scriptures, that chanting the Holy Name of the Lord is the process for all religions.
21 July 2005.
19+ minutes, 4.6 MB mp3 audio.

Srila Vyasadev. Selected excerpts by Srila Bhakti Raksak Sridhar Dev-Goswami Maharaj taken from the Sermons of The Guardian of Devotion series and Sri Guru and His Grace.

Srila Sanatan Goswami. Excerpts from Sermons of The Guardian of Devotion Volumes 1 and 2 by Srila Bhakti Raksak Sridhar Dev-Goswami Maharaj.

Audio: Vedavyas had so much experience. Informal discourse by Srila Bhakti Sundar Govinda Dev-Goswami Maharaj at our Dum Dum Park Temple, Kolkata, 24 July 2006.
Download, or listen online (13 minutes, 1.6 MB mp3 audio)
or:
higher quality (3.1 MB)

A short excerpt about chaturmasya by Srila Bhaktivedanta Swami Prabhupada in his edition of Sri Chaitanya-charitamrita (Madhya-lila 4.169).

Audio: Beginning of Chaturmasya, the four months of the rainy season. Early morning informal discourse by Srila Bhakti Sundar Govinda Dev-Goswami Maharaj, 11 July 2006, on his veranda at our Dum Dum Park Temple, Kolkata. The background sound is rain falling on the neighbouring roof.
Download, or listen online (16+ minutes, 1.9 MB mp3 audio)
or:
higher quality (3.9 MB).

Sanatan Goswami and the sweet-rice from the book 'Dignity of the Divine Servitor' by Srila Bhakti Sundar Govinda Dev-Goswami Maharaj.