4, 2, 3, 7.
That's how you offer the lamp to a Hindu god.
Puja, also known as arati, is the major Hindu rite of temple service, in which various items—water, incense, fire, a flower (read: water, air, fire, earth) are presented to the deity indwelling the murti (statue), and then consumed by the worshiper herself.
(There's an entire theology encoded in this ritual, but I'll leave you to suss that for yourself.)
Each item is circled in the air—sunwise, of course—before the deity a certain number of times. That's where the numbers cited above come in.
- Four small circles to the god's feet.
- Two small circles to the god's navel.
- Three small circles to the god's face.
- Seven large circles around the god's entire body.
Why, I asked my friend, head pujari at the local ISCKON center, those particular numbers to those particular parts of the god?
My friend didn't know. He had, in fact, asked the same question of his teacher, who likewise did not know. While in altar training, my friend had asked all around. No one in the community seemed to know.
(This isn't really surprising. Sometimes things become so ingrained in a tradition that it simply never occurs to anyone to ask.)
Sometimes it takes an outsider to see to the heart of a given matter. I'm a ritualist myself, of a different, though related, tradition. So here, for what it's worth, is my best guess as to the meanings: