Various Hindu deities are shown holding various weapons. Just as scriptural stories are metaphors for the interactions between various good and evil forces within us, weapons of deities also have a symbolic meaning.
To illustrate this, let us take the weapons carried by 2 graha devatas (planetary deities) - Mangala (Mars) & Sani (Saturn). Mangala carries a gada (mace), while Sani carries bow and arrows. (Note: Some people show Sani with a trident, but his 108 name prayer says “shara tUNIra dhAriNe”.)
Now, think of how the 2 weapons are used. Gada is used in close combat where heavy blows may be exchanged. Thus, it involves boldness, risk taking and aggression. THAT is the nature of Mangala! After all, Mangala is a personification of qualities within us such as aggression, boldness, energy, drive and taking initiative. No wonder the weapon reflects that.
In contrast, Sani is the planet of patience, focus and persistence. Accordingly, his weapon is bow & arrows. After all, that does not require close combat. One can stand at a distance or even hide and fight. Killing with bow and arrow requires focus and patience - one waits for the right time to shoot arrow and needs good focus to shoot the target. Accordingly, Saturn is not the planet of aggression and bravery, but of patience and focus.
Lord Vishnu governs doing one’s dharma in the universe and dharma is basis of sustaining oneself. Doing one’s dharma requires the ability for patient waiting game as well as bold confrontations. So Vishnu carries both Gada and bow. In addition, he carries Sankha and Sudarsana Chakra. Sankha or conch symbolizes clearly declaring intention. Doing one’s dharma also requires clear vision of what is permanent and what is impermanent. Sudarsana (literally, “good vision”) chakra stands for cutting off attachments and agendas and seeing one’s role in the world with abolute clarity. Thus, Vishnu’s weapons represent, seeing one’s dharma clearly, declaring one’s intentions loud & clear, fighting obstacles boldly, aggressively and also patiently.
Lord Ganesha rules over Mooladhara chakra or earth element, i.e. stability and groundedness, which come from being able to resist and overcome disturbances, distractions and obstacles. He carries noose (paasha), elephant goad (ankusha) and axe (parashu).
Noose symbolizes attraction and focus on something, which is key to stability and focus. Attraction to something, whether mundane or spiritual, causes the “gravity” to pull one to it, keeps one engaged and causes stability.
Elephant goad symbolizes controlling and directing the mighty force of groundedness. Lazily sitting in sofa is one kind of groundedness (but tamasik) and doing an important work with focus, enjoyment and stability is another kind of groundedness. The mighty elephant of groundedness needs to be controlled and directed. Elephant goad symbolizes it.
Axe (parashu) has a dual role. Like a sword, it can cuts off distractions. In addition, like a chisel, it can be used to shape and fine-tune. Cutting off distractions and fine-tuning the desirable aspects enhance stability and groundedness.
If one takes Matangi (one of Dasa Mahavidyas), she wears a veena (stringed musical instrument), a parrot, a sword and a skull. Veena is a symbol of skill and ability. Parrot symbolizes external speech. Sword is for cutting off attachments. Skull shows destruction of ego (lifeless head!). Matangi is similar to Sarawswati, goddess of learning. While Saraswati holds veena and book (skill & knowledge), Matangi wears skull and sword too, like Kali and Tara. She shows learning and good ability to speak (or write), but with detachment (sword) and with a depleting ego-sense (skull).
One can ponder over the weapons of various deities like this. Before closing this, let me take a more complicated example.
The “Pradhanika Rahasya” (main secret) of Durga Saptashati describes the supreme Mother of 3 Gunas, who divided Herself into 3 supreme goddesses. This “original goddess” wore a few interesting weapons in her arms - fruit, mace, planet, wine bowl, serpent, male genital, female genital and king’s head.
As She is the source of duality and division in Self, her weapons have to reflect the forces that create and maintain duality and division in Self. I’ll leave it to you to ponder what the 8 items mentioned above symbolize!