First of all, Sun is light, fire and energy, so when exalted sun will transit 8th house which is the house of fear, worries, uncertainty, transformation, up n down, mystic and occult energies, Sun will shed its light on your insecurities, fear, uncertainty. So you will be able to all negativity, fear, etc which was already there but you were unaware. So first of all there will be sudden reality and insecurities And then you will be able to confront your fears with your confidence and aura. So fears, insecurities will come in front, so you will be able see your dark areas. So there will be realisation of fear.

Sun will burn all your negativity. There will be more confidence, knowledge and security.

You may feel more clear, certain and as sun is friendly to mars so it will ignite martian occult knowledge. Sun will illuminate the native with hidden knowledge too.