Focussed Burst, if you hit jump again when you hear the swish you can move around pretty fast (for a warlock) and you don't float around like a balloon asking to be shot
This is my sunsinger build (pretty much the meta)
https://www.bungie.net/en/Legend/Gear/2/4611686018437613279/2305843009230755270 if you check the skill tree that's for PvP, for PvE I switch to fusion grenades, scorch melee for orbs and gift of the sun
If you're Sunsinger you want T5 Disc/Str, Voidwalker T5 Int/Disc and Stormcaller T5 Int/Str