Karthigai Deepam: Celebrating Divine Light with Murugan Homa

Karthigai Deepam is among the oldest festivals still kept in Tamil Nadu and across the Tamil-speaking world. It falls in the Tamil month of Karthigai, which spans mid-November to mid-December, on the day of the full moon (Purnima) when the nakshatra Krittika is current. Homes and temples are filled with rows of oil lamps, and the festival is held as a celebration of divine light — knowledge over ignorance, and the presence of the sacred in ordinary life.

The day is linked both to Lord Shiva, remembered as the infinite pillar of light at Arunachala, and to Lord Murugan, whose birth is traditionally associated with the six Krittika maidens. Alongside the lighting of deepams, many families and temples keep a fire rite dedicated to Murugan. Tradition treats that homa as a way of joining the festival’s outer lamps with an inner offering into Agni.

This article sets out what Karthigai Deepam is, why Murugan and Shiva are remembered together on this tithi, how the day is observed at home, and what the classical Murugan fire rite involves — without padding, booking rails, or claims the rite cannot make.

What Karthigai Deepam is, and when it falls

Karthigai Deepam is fixed by the lunar calendar, not the civil one. It is observed on Karthigai Purnima — the full-moon day of the month named Karthigai — when the Moon is with the star Krittika. The same star gives the month its name. Because the Tamil calendar and the Gregorian calendar drift against each other, the English date moves each year within November and December; the sure way to know the day is to check the festival calendar or the day’s panchang for tithi and nakshatra.

In temple and household practice the festival is older than many better-known Deepavali customs of the north. Classical Tamil literature already speaks of lighting lamps in Karthigai, and the rite has remained continuous in Shaiva and Murugan centres across Tamil Nadu and Kerala. The outer act is simple: clean the house, draw kolam, fill earthen agal lamps with oil or ghee, and light them after sunset. The inner meaning, kept by the tradition, is the honouring of light as a sign of the divine.

Shiva as the pillar of light, and the Maha Deepam

One strand of the festival’s meaning comes from the well-known Puranic account of Shiva as an endless column of fire — the lingodbhava — which neither Brahma nor Vishnu could measure. That form is especially remembered at Arunachala in Tiruvannamalai. On Karthigai Purnima the temple lights the Maha Deepam on the summit of the hill: a great flame visible for miles, treated by devotees as a public sign of that formless light.

Even for those who cannot travel to Tiruvannamalai, local Shiva temples light deepams, perform arati, and recite the names of Arunachaleswara. Households place a main lamp at the home altar first, then light the remaining lamps at the doorway, courtyard, balcony and rooftop. The sequence is deliberate: the altar lamp stands for the presence of the deity; the outer lamps carry that presence into the dwelling and the street.

Lord Murugan and the Krittika connection

The other strand of the day is Murugan. In the Skanda tradition, the six sparks from Shiva’s third eye were received by the six Krittika maidens, and from them the child who became Shanmukha — Murugan, Subramanya, Kartikeya — took form. Because the festival is timed to Krittika nakshatra, Murugan is remembered with particular warmth on this Purnima. He is invoked as the lord of the Vel, the commander of the divine hosts, and the teacher of wisdom.

Devotees who wish to know whether Krittika is their own birth star can check it on the nakshatra finder. Those born under Krittika sometimes keep an additional observance through a Krittika Nakshatra Homa, which the tradition groups with other nakshatra fire rites. On Karthigai Deepam itself, however, the wider custom is simply to light lamps for Murugan, recite his names, and, where a priest is available, to offer a homa into the sacred fire.

How the day is kept at home

Household observance follows a clear order that needs no temple apparatus, though many families also visit a nearby Shiva or Murugan shrine in the evening.

• Cleaning and kolam. The house is swept and washed; rice-flour kolam is drawn at the threshold and before the lamp-stand. The cleaning is treated as the removal of dullness from the place where light will be invited.
• Preparing the agal lamps. Earthen lamps are washed, filled with sesame oil or ghee, and fitted with cotton wicks. Rows are set at the altar, entrance, windows and open terraces.
• Lighting after sunset. The main lamp at the altar is lit first, with a short prayer to Shiva and Murugan; the remaining lamps follow. Many households keep the lamps burning into the night.
• Naivedyam and simple fasting. Some observe a light fast until evening. Traditional offerings include pori urundai, adai, jaggery sweets and payasam, presented as naivedyam and then shared as prasadam.
• Slokas. Common recitations include Om Namah Shivaya, Murugan’s names such as Om Saravanabhava, and the short Karthigai deepa hymns used in Tamil homes.

None of these steps requires a specialist. They are the ordinary grammar of the festival, kept whether one is in Chennai, Coimbatore, Singapore or New Jersey.

The Murugan homa on Karthigai Deepam

Where a Vedic fire rite is arranged for the festival, it is offered to Murugan. The structure is the standard homa form: sankalpa, pratishta of Agni, invocation of the deity, offerings of ghee, herbs and grains with mantra, and a closing purnahuti. The fire is treated as the mouth of the gods; what is given into it is understood, in the classical view, to be carried to the deity named in the sankalpa.

Mantras used in Murugan rites commonly include the Saravanabhava bija and passages from the Subramanya corpus. A short form many households already know is:

At the ashram, priests perform such fire rites live and telecast them to devotees who cannot be present in person. A Subramanya-facing rite kept in the catalogue is the Shatru Samhara Subramanya Trishati Homa; related observances for protection and inner steadiness are grouped under the house’s protection homas and spiritual-growth homas. Tradition prescribes these rites as offerings of devotion and as petitions for Murugan’s guidance; the house performs them with the sankalpa the devotee names, without attaching guarantees to the flame.

What the festival asks of the devotee

Karthigai Deepam is not a complicated liturgy. Its demands are few and concrete: clean the place, light the lamps on the correct tithi, remember Shiva’s light and Murugan’s Vel, share prasadam, and — if a homa is undertaken — offer it with a clear sankalpa. The festival’s own language is the language of light. Scripture and custom treat that light as a sign of awareness; the lamps and the fire are the means the tradition has kept for marking it once a year.

For anyone unsure which observance fits a particular chart or family custom, the free guidance desk at Ask Nirnaya can point to the relevant rite. The date itself remains a matter of the panchang: Karthigai Purnima, Krittika in force, lamps after dusk.

Questions devotees ask