According to our almanac every three years, one month is added. This is done to harmonize the lunar month (chandra-maas) with the solar month (saur-maas). The inserted month is known as 'Purushottam', and is technically called an 'intercalary month'.

Purushottam is the most congenial month for the bhakti-sadhan. Even the aparadhas(offences) can be pardoned if we do devotional practice in this month. The adhishthata(presiding deity) of this holiest of all months is Bhagavan Sri Purushottam (Sri Krishna) Himself. So, of all the months, this month is the most favourite of the Supreme Lord Sri Krishna. The sadhana performed in this month will have a manifold result.

Everything has got consciousness in the background, as per our scriptures, the example is given of the sun, which is presided over by the Sun god, the moon which is presided over by the Moon god and Srimati Ganga Devi, who is the presiding Deity of the river Ganga. Similarly this Purushottam month has a presiding deity.

Being depressed due to her seemingly useless existence, the personified deity of this month approached Lord Narayana. This incident is described in the scriptures. She went to Narayana, asking, “What offence did I commit? No one is performing any pious activities during my time. Why?”

Lord Narayana directed her towards Lord Krishna: “You come with Me, I shall take you to Lord Krishna.”

Upon being approached by her, Lord Krishna responded: “I am Purushottam and I cannot be comprehended by finite beings of this world. They cannot comprehend Me by their mental comprehension and sense organs as I am beyond these means.”

Krishna explained: “This additional month is like Me. I cannot be comprehended by the conditioned souls of this world and I am supremely superior to Brahman and Paramatma so I am designated as ‘Purushottam.’ You are identical with Me. You are the holiest month. If anybody observes vrata (vow of austerity) during your time, he can get everything. If as by scriptural injunctions he observes it, it is even more auspicious than Kartik-vrata, the holiest month. So you will be known by the name ‘Purushottam’.”

The Lord of the Universe—Sri Jagannath Dev is also known as Purushottam. Puri is known as Purushottam Dhama. Sree Chaitanya Mahaprabhu used to sing Sri Jagannath-ashtakam, eight verses of the glory of Jagannath Dev in Puri. So, we may recite the same Sri Jagannath-ashtakam in this Purushottam Month.

Observe the entire month same as Kartika by fasting from tomatoes, eggplants, sesame and mustard seeds, and sesame and mustard oil, honey and urad-dahl. We shall read the glories of Purushottam-vrata, from the writings of Sri Bhaktivinoda Thakur, in the morning; daily recite 'Sri Jagannathastakam' and 'Chauragraganya Purusashtakamas' in the afternoon and perform silent Japam of sloka instructed by Kaundinya Muni:-

govardhana-dharam vande gopalam goparupinam,
gokulotsavameeshaanam govindam gopikapriyam.

In the evening, offer a lamp of pure ghee to Lord Vishnu (in a temple of Lord Vishnu, Krishna or Rama or any of Dasavatara), Lastly, at night to read 'Brahmastava' 40 shlokas, from Srimad Bhagwattam, Chapter 14th, Canto 10th.

vande navaghana-syam dvibhujam murlidharam
pitambardharam devam saradham purushottam

"I offer my obeisances to Navaganasyam (Krishna, who has the color of a fresh rain cloud), who is holding the flute with His two hands. I worship Purushottam who is so beautiful in His yellow dress (pitambara)."

Devotees concentrate on worshipping the Supreme Lord by hearing, chanting and remembering the name, form, pastimes and qualities of Sri Krishna day and night for spiritual benefit only. Reasoning correctly that any tendency for material benefit will certainly divert their minds, they observe this vrata by hearing about Krishna, chanting the Mahamantra and taking Prasadam. Srila Bhaktivinoda Thakura recommends to follow this path.