The word "Thiru" translates to holy. The word "Pavai" refers to the rituals performed by unmarried girls to God to uphold a vow. Pavai is also a genre. It is the melodious singing of songs by the devotee to please God.
One popular religious observance kept by people of Southern India is the Dhanurmasam month, also known as the Pongal Month. During this month, devotees sing Thiruppavai hymns, one each per day, for 30 days and offer the Pongal as Naivedyam to Lord Krishna/ Lord Ranganatha Swamy.
Dhanurmasam is the name of a solar calendar month that falls between the 15/16th of December to 14/15 th of January. It is the Sagittarius month. It is also known as "Margazhi" month in the Tamil Calendar.
Pongal is a recipe prepared during this month by the devotees with rice and split moon dal (cooked well in steam) and then topped with pepper, ginger, cashew nuts, cumin, etc. This Pongal is offered to God as naivedyam after the worship during these 30 days. So, it is known as Pongal Month also.
Now, coming to Tiruppavai, the original ritual was performed by a saint known as Goda Devi to uphold her wish to marry God. She is a Tamil saint born in Sri Villiputtur, Tamil Nadu, in the 8th century CE. She was a priest's daughter and naturally was attached to God from her childhood. She loved her God so dearly that she vowed to marry Him only and performed the ritual of worshiping God in the form of Krishna assuming herself as a cowherd. She created verses, one each per day for 30 days, and sang them melodiously with pure devotion abstaining from all worldly desires. She invited other maids from her village also to join in her worship. She offered flower garlands after testing them herself to assure herself they were fresh and good. In the end, she got married to the Temple God Ranganatha Swamy in Sri Rangam as per the wish of God (who appeared in a dream to her father and ordered him to do so) and transformed into an idol beside him in that temple.
From that period onwards, the devotees started to perform this ritual during the same period every year worshiping Goda Devi as Andal (or as Ranganayaki Taayar) and Lord Ranganatha Swamy.
During this period, we worship Vishnu in the form of Sri Ranganatha Swamy or Krishna and Lakshmi as Andal or vice versa. Each day, we chant one Pasuram from Tiruppavai (chronologically) and offer Pongal as naivedyam to God after the worship. It culminates on the final day as Makar Sankranti.
Tiruppavai Essence
Thiruppavai is a profound expression of Vedic knowledge, summarized in 30 hymns. On the surface, it involves the performance of rituals through the chanting of hymns and observing fasts to attain material benefits, such as enjoying a feast with Krishna or receiving a small drum-like instrument from Him. However, if you delve deeper, you will discover the true treasure: a transcendental spiritual reunion with God. It requires a lot of deep meditation into the meanings of each hymn.
For the time being, I am providing the general layman's perception of the significance of Tiruppavai.
Tiruppavai contains 30 hymns which are to be recited daily during the month of Margazhi (Dhanurmasam) with true devotion to God for attaining some spiritual benefits. It was performed by Andal, a divine saint, more than a millennium ago to marry Lord Krishna (replicating the ritual performed by Radha and other Gopis during the Dwaparayuga). So, if we observe this ritual, we too can attain a reunion with God.
The first five hymns of the Tiruppavai introduce the main theme of the ritual. They emphasize the importance of maintaining purity in both body and mind and of abstaining from all material pleasures during the Margazhi season. Devotees are encouraged to focus on the virtues of God and to sing songs that glorify Him. Offering flowers to God is also an important practice. By engaging in these actions, the sins from both our past and present lives can be eradicated through God's grace. Ultimately, He will grant us the Parai, which represents the eternal blissful reunion with Him.
In the next ten hymns (hymns 6 to 15), Andal emphasizes the awakening of her friends, encouraging them to take a purifying bath, wear clean clothes, gather flowers, and perform the ritual together so that everyone can benefit from it. She inspires each gopika by reminding them of their inherent virtues and urges them to leave their homes to participate in the ritual and enjoy its spiritual rewards.
Andal describes the natural daily life and activities occurring in the surroundings, such as the blossoming flowers, the chirping of birds, the churning of milk, the ringing bells around the necks of the cattle, the echoes of temple bells, and the melodious tunes sung by the sages visiting the temple. She points out to her companions that all of these elements are signs of the approaching dawn and the time for worship.
Hymns 16 to 20 describe her visit to the temple. The temple in this case is supposed to be that of Lord Krishna's house. She approaches the gate along with her companions and requests the guards to open the gates as she, along with her friends, likes to sing the awakening songs to Lord Krishna. She awakens Krishna's father and mother, and brother Balarama along with Krishna. But, She needed to awaken Niladevi before Krishna. So, she awakens her in the stanzas 18 to 20.
The last nine Pasurams (21 to 29) deal with the glorification of Krishna's virtues. In the 27th pasuram, Goda Devi enlists her desires to feast with him. The 28th and 29th Pasurams describe her ignorance and her surrendrance before Him.
The 30th hymn is a concluding envoie attesting herself as the daughter of the temple priest, Vishnu Chitta, and the assertion that whoever sings these 30 hymns with pure devotion to God will attain Krishna's grace.
For Tiruppavai Pasurams (with full meanings), you may go to this link and read the hymn you want.
