The "green way" is unlike the other four cosmic routes of the universe -- the red way (camino rojo/ꜫaꜫabe, or kaq bej in modern orthograph), black way (camino negro/queca be/q’eq bej), white way (camino blanco/zaqui be/saq bej), and yellow way (camino amarillo/ꜫana be/q’än bej). In linguistic and cultural terms, green (rax in K'iche', yaax in Yukatek) represents newness or "primary" states within Maya cosmovision (Ajpub' Pablo García Ixmatá 2010: 227).
These four routes refer to the four cardinal points; the color symbolism often aligns with particular directions. In hieroglyphic writing traditions from Mesoamerica, we often find that red is associated with the east; black, the west; white, the north; yellow, the south (Johnson 2013: 242). Although these colors refer to much more than cardinal points, there is a core geographic orientation (Houston et al. 2009; Tokovinine 2012). In other words, because each cardinal direction is linked to specific color symbolisms, color serves as a mechanism through which Maya speakers situate themselves in geographic or physical space and connect with the spirit world of the nawales (May K’iche’ Winaq B’elejeb’ Aj | unión de escritores mayas, Raxalaj mayab' k'aslemalil | Cosmovisión maya, plenitud de la vida, esp. 30-33).
But the "green way" (camino verde/raxa be/räxal bej) is unlike these other four cases.
For one, its range of meanings is quite broad. The word "räxal" (rax) means both "blue" and "green," such that speakers of K'iche' and other Mayan languages distinguish between, as Christenson (2007: note 22, page 53) puts it, “'räx like the sky', for blue, or 'räx like a tree' for green." Christenson (2007: note 832, page 272), glossing the prayer that K'iche' leaders offer to Juraqan and Uk'u'x Kaj Uk'u'x Ulew explains that räxal, or "green/blueness,” connotes "vitality, newness, freshness, fertility," and that its meanings change when combined with other color properties. For example, "The combination of green and yellow is still used ceremonially to refer to the concept of 'abundance. Thus in the prayers of Quiché aj q'ij priests, the litany of deities they invoke include the “green shoulder, yellow shoulder of the world,' described as “the procreative powers of the earth” (Bunzel 1952, 266)."
For another, its written name seems to have changed to reflect some of the ways in which blue/green objects were used. As Houston et al. (2009: 40) explain in their study of the term yax (blue/green) in hieroglyphic inscriptions, "Maya scribes decided at some point to clarify the spelling further by inserting the [xa] syllable, a sign that owes its origin to the depiction of a rattle" and suggests onomatopoeia, because "the [xa] recalls the sibilant tones of gourd rattles."
Sam Colop (2011: nota 149, página 221) explica que el "camino verde" representa "el 'centro' y que sustituye al color amarillo 'sur'", precisamente en el momento en que los gémelos divinos vuelvan a pasar por la encrucijada de Xibalba, el mismo espacio por el cual Junajpu y Wuqub Jujapu ya pasaron. Ahí, pues, "Se sigue una oposición de colores comenzando con el negro, camino que marcó la muerte de sus padres, luego viene el blanco, el rojo y el verde, siendo este último el 'camino de la vida' y centro del orden cósmico maya. De aquí que el orden con que se nombra a los caminos en este pasaje, tiene una intencionalidad subyacente: no perecer, como efectivamente sucede."