A Havan (fire sacrifice altar) has three zones which is the form of triguṇātmikā prakruti (the three qualities of nature).The one at the bottom is painted black, the middle one is painted red and the topmost is painted white. Why?
Black represents tamoguṇa (the mode of inertia), red represents rajoguṇa (mode of passion) and white represents sattvaguṇa (mode of goodness).
The Vedikā (platform of the altar) is the form of prakruti (force of nature) and the fire inside is the Puruṣa (the Supreme Being). The white zone, sattvaguṇa, is the closest to God.
This is why devotees on the spiritual path must first reduce their tamoguṇa (the mode of inertia), then rajoguṇa (mode of passion) and their nature should dominate in sattvaguṇa (mode of goodness). You see sages being calm in nature due to sattvaguṇa.
The last step from this makes one bhramarup (one with God). This is the science of Yagya.
