Concat doesn't seem to work on a JSON obtained array
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I'm having a some trouble with the concat function in javascript.  As far as I can tell, I'm using it correctly, but it's not successfully concatenating the array "value" from the JSON onto the array "currentAbilities":  

    $.each(ABILITIES, function(key,value) {
            if(key==raceName||(key==className&&(!isAcolyte)))
            {
                document.getElementById('abs').innerHTML = value[1];
                currentAbilities.concat(value);
            }
        })

The innerHTML setting line shows that the array "value" does exist.  Any idea why I'm failing to concat?  Value of course comes from a JSON, could that have anything to do with it?  I'm afraid I only recently became familiar with $.each and JSON usage and may be doing it wrong.