The glow is the enchantment on your weapon.
Some skills can activate a glow on the weapon too : Molten Armaments of the Dragon Knight (if a DK cast it near you, you'll be affected), Evil Hunter (Fighter's Guild tree), Siphonning Attacks (Nightblade Siphonning tree)
Templars don't have any.
By the look of your screen, it looks like a fire enchantment. Check your weapon, you probably have one
The glow is the enchantment on your weapon.
Templars don't have any.
Its a visual effect to make you know that the empower is active.
Empower- increases your damage of your next attack by 20%
So, it grants you Empower similar to inner light.
Enraged_Tiki_Torch wrote: »You can "bug" out the empower effect on your weapon to keep it for however long you like. I do it by Dark Flare, charge heavy attack and then as Dark Flare hits, Puncturing Sweeps. Timed right, you can keep the effect which is cool to run around with a glowing weapon. You don't keep the empower buff though, it's just a weapon effect bug.