Gold is easy…aside from it’s earthly value, gold represents the heavenly kingdom.
Frankincense represents Christ being the priest (our intermediary between God and us). The tree that produces frankincense resin tears is known to be so hearty that it grows appendages to attach itself to rocks where there is no soil or water available. Frankincense represents new life and new birth….it is used to anoint new infants and those moving spiritually into a new aspect of life
Myrrh is the obscure one here. It is worth it’s weigh in gold and is 5 times more valuable than Frankincense. However, myrrh is associated with death. It is burned at funerals to mask the aroma of the corpse. Amazingly, myrrh has life-giving medicinal qualities. It would have been used by Mary in post-partum healing. It is a known disinfectant. It has been used for heart, liver and spleen ailments as it is known to increase the heart rate and improves circulation. Spiritually, it represents the death and rebirth of our Savior. And if you think about it, myrrh would be appropriate. Jesus had to leave (figurative die) heaven to come to earth (left heaven, reborn on earth). Then in 33 years he is crucified, laid behind a stone and rose in 3 days (death and rebirth).