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

Question

Our group found a Beacon of Erathis^DDI 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

From page 236 of the PHB:

If you are a member of a class that can use a holy symbol as an implement, you can [...] use a holy symbol's properties and powers. Members of other classes gain no benefit from wearing or holding a holy symbol.

[...]

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 specifically use holy symbols as implements (it isn't enough just to be able to use implements), and who are the same deity as the symbol, may simply wear it. They don't need to keep it in hand to activate or use it.

2. You only get the bonus to powers with the implement keyword, and only for powers belonging to a class that can use the holy symbol as an implement. From the PHB:

   You can apply the enhancement bonus of a holy symbol to the attack rolls and the damage rolls of any of your powers from [a class that can use a holy symbol as an implement] that have the implement keyword.

3. You use a power with the restrictions mentioned above, which deals fire or radiant damage. So your fighter would only be able to access this ability via multiclassing. Even then, he wouldn't gain the benefit to any of his fighter powers or basic attacks (although he wouldn't need to hold it in his off hand).

4. I don't know. Multiclass feats into Cleric or other holy symbol wielding classes, I suppose.