Rudra (Devanagari) is a Rigvedic God, associated with wind or storm and the hunt. The name has been translated as "The Roarer", or "The Howler".
The theonym Shiva originates as an epithet of Rudra, the adjective shiva "kind" being used euphemistically of the god who in the Rigveda also carries the epithet ghora "terrible". Usage of the epithet came to exceed the original theonym and by the post-Vedic period (in the Sanskrit Epics), the name Rudra is taken as a synonym for the god Shiva and the two names are used interchangeably. Shiva is known as the destroyer, regenerator God. Something has to be destroyed to make room for change or regeneration.
In RV 7.46, Rudra is described as armed with a bow and fast-flying arrows. Rudra discharges "brilliant shafts which run about the heaven and the earth" (RV 7.46.3), which may be a reference to the destructive power of lightning. (Wikipedia reference).
It sometimes feels like you have been struck with a bolt of lightening, out of the blue, when Shiva shows up in your life. This lightening aspect of Shiva reminds me of the story of Mahavatar’s “burning branch” with which he is reputed to have struck a disciple once. Mahavatar gave the gift of taking the man’s karma along with giving the burn, and thereby the man received the gift of enlightenment and immortality.! Of course, that was the last bit of the man’s karma as he perhaps had worked many lifetimes in balancing his karma. As Babaji often says on this blog: “It is time.” Swami Vishwananda says: “Everything happens in Divine timing.” When we are stuck in ego, we won’t let go, because the price seems to high. It is difficult of mankind to let go, even when letting go of ego-based desires bring greater gifs such as Swami Vishwananda teaches: “What do you have when you have, God? The answer: “Everything.” -Utpalavati