I always wonder why Hindu Gods carry weapons. I mean they are "Gods", why do they need weapons?
First I feel the terminology of "God" is unsuitable. Unfortunately in English there is no proper translation of Devtā. Deity is closer.
In Hinduism devās are seen as friends and guides and hence human qualities were projected on them. This can be seen throughout the Rig Veda. Hinduism evolved from tribal roots and also assimilated tribal cultures into it. The deities are thus portrayed as how a human helper or a protector would be - with weapons.
The Rig Vedic people didn’t worship in temples but did in fire altars. Given that temples were a later development, lots of metaphorical and philosophical ideas had developed behind the iconography.
In the book "Hindu Iconology - The study of the symbolism and meaning of Icons", Pandit Sri Rama Ramanuja Achari outlines the symbolic meanings behind many aspects of Hindu iconography.
Here are some of them:
For further information on Hindu iconography refer to this e-book.
Sometimes even the weapons themselves are given human form. For example Sudarshana Chakra is given anthropomorphic form and known as Chakkrath Azhwar in Tamil.