"A channeled skill is a skill with a long casting duration that constantly applies some effect while it is being cast, rather than causing that effect at the end of its cast as normal skills do. Every time a player channeling a skill is hit, the spell loses some of its total duration, so that a character under heavy and rapid attack that begins a channeled skill may find its effective duration reduced to practically nothing. Stunning a player in any way while they are channeling a skill instantly ends the channeling without restoring the skill's cooldown. "
from
http://lotro-wiki.com/index.php/Channeled_Skill
couldn't have said better myself. if you've ever played mmorpg games before, you'll know what they are talking about. DotA has tons of channeling skills.. though an atk/stun etc will interrupt it there. Not sure about here.
INT/MATK i agree
slayers also agree
sacrifice - does magic damage to a single enemy target. restores of portion of damage done as health to the caster. (60% damage as hp lv1)
so if you do 1k damage, ull get 600hp back. 10k dmg, ull get 6k hp back.
demons grasp - channeling skill. stuns target for a short period of time during channeling. lasts 4seconds.
so this you will stun a target while you are channeling this skill. a good way to think of channeling is 'using'. if i throw a bucket of water at you, thats just a skill. if i continuously spray you with a water hose for 4 seconds, thats channeling. i can cancel the water at any time. if you tie a knot (aka stun) in the hose, it will also stop. you can move as well to stop channeling. basically you and ur target are both 'stunned' persay for that 4 seconds, but you can do something about it, they cant. once u do anything else, the channeling stops.
i hope this helped. im not a priest but i have exp[erience with mmorpgs. anything you dont understand lemme know ill try to explain better xD