Beacon of Erathis, or What boons does an Implement grant a non-cleric?

Question

Our group found a Beacon of Erathis, an Implement (Holy Symbol) which grants:

Enhancement: +1 attack rolls and damage rolls

Critical: +1d8 fire damage

Power (At-Will): Minor Action. The holy symbol sheds bright light to a radius of 20 squares. You can douse or reactivate the light as a minor action.

Power (Daily): Free Action.
Trigger: You hit an enemy with a fire or radiant attack using this holy symbol.
Effect: The creature you hit sheds bright light to a radius of 20 squares and grants combat advantage (save ends both).

We don't have a cleric, or any character that has the Implement keyword appearing in any of their powers. [This seems a bit odd, given we have an essentials Sentinel with us.] If any of us want to use this item, what boons does it grant, and under what conditions?

1. The only thing we're sure of is that we can use it as a bright light source, but even it that case the card doesn't make it clear if we have to hold it to use activate or continue using that ability. For example, can our Sentinel wear it around her neck on a chain, grab it to [de]activate it and then let it hang glowing around her neck?
2. Does the +1 attack/damage apply simply by possessing the item? Do you have to hold it? Do you have to attack with it (requiring the Implement keyword)?
3. None of our characters have fire or radiant attacks, yet - but if we did, what does "using this holy symbol" mean in the daily power described? Does it mean a fire/radiant attack power with the Implement keyword? Or could a fighter with a flaming sword hold this in his other hand for this benefit?
4. Are there any ways [powers?feats?] to make this item fully useful to low level character?

We'll probably keep it as a permanent bright light source (unless we're wrong about #1) - but clarification on the other questions would be helpful in our understanding of the game mechanics.

Answer 1

Player's Handbook 2 (released in March 2009) changed how implements work. Now you only have to be proficient with holy symbols, but need not belong to such a class. You can use any implement power with any implement you are proficient with. A multiclass feat is sufficient.

From page 236 of the PHB:

Unlike other implements, you need only to wear a holy symbol for its property or power to function. If you are wearing or holding more than one holy symbol, none of your symbols function.

So, to answer your questions:

1. Characters who can use holy symbols as implements (it isn't enough just to be able to use implements), may simply wear it. They don't need to keep it in hand to activate or use it. They do not have to worship Erathis either. Note the difference in the description of Leaves of Death:

   Requirement: You must worship the undying court to use this holy symbol.

2. When you use an implement power, while wearing this holy symbol, you gain +1 to attack rolls and damage rolls.

3. You use a power with the restrictions mentioned above, which deals fire or radiant damage. So your fighter with the Order Adept theme and the Disciple of Divine Wrath feat can use the Argent Rain power with this holy symbol. The theme provides a fire implement power, and the feat gives proficiency in holy symbols.

4. Take a multiclass feat into Cleric or other holy symbol wielding classes.