When it comes to rules, there is the letter and then there is the spirit.
Sometimes they are one in the same. Other times, there is a difference.
An example of that difference emerged this last week in the retail sector, as Level 5 restrictions came into place around the country.
All but non-essential retailers were supposed to close, and for the most part they now have.
But certain shops that either inhabit a grey area, or in some cases appear at least to ordinarily sit squarely in the "non-essential" category, have remained open.
They are justifying this; it's claimed by those unhappy with the situation, by carrying some essential stock like PPE and food for example, among predominantly non-essential items.
It has also been alleged that some essential retailers who carry smaller amounts of non-essential goods are continuing to sell them.
Some may genuinely believe they are acting legitimately within the rules. Others though may be just trying to push the boundaries.
Either way, the situation has generated significant and understandable resentment among particularly smaller specialist retailers who have followed the public health rules to the last, closing their doors and in many cases laying off staff.
They claim everyone should be abiding by both the spirit as well as the letter of the rules.
These store-owners say that by opening when they shouldn’t, or selling stock that isn’t classed as essential, their competitors are gaining a significant upper hand in the lucrative run-in to Christmas.
Unlike when the country went into the highest level of restrictions back in March, this time round the rules around retail are pretty clear, as are the detailed descriptions of what constitutes essential and what doesn’t.
Under the Level 5 restrictions, retailers with a mixed retail offering which have discrete spaces for essential and non-essential retail, should make arrangements for the separation and closure of non-essential retail areas, they state.
That should for the most part be reasonably achievable, although in circumstances where essential and non-essential stock was genuinely intertwined before the restrictions came in, it may be justifiable to leave it so.
Retail Excellence, which represents more than 2,000 retail businesses across the country, says its membership is angry about the situation.
It is asking the Government to intervene, saying the actions of those not abiding by the rules is akin to rubbing salt in the wounds of others that are.
It also claims that in cases where restrictions are circumvented, thereby enticing people to travel and shop for non-essential items, it risks the whole purpose of the shutdown.
That in turn could jeopardise the hoped-for reopening of the retail sector for all outlets in just under five weeks time.
Small business organisation, ISME, has gone further, claiming that if it is not resolved, the situation could lead to "civil disobedience" by some small and increasingly angry retailers.
The Government is well aware of the issue and is understood to be working behind the scenes to resolve it in a non-confrontational way.
Both Tánaiste Leo Varadkar and Minister of State for Business, Employment and Retail, Damien English have made public and private appeals to all retailers to stick to the spirit of the guidelines.
Well-placed sources indicate if compliance is not achieved through this type of engagement in the very near future, then other measures will have to be looked at.
That might mean garda inspections of retail outlets, for example, a path the Government will be keen to avoid going down if at all possible.
Because, apart from the unattractive spectre of a showdown with businesses, there is also the difficulty that some members of the public may actually support the actions of retailers that are bending or breaching the rules.
In Wales, for example, thousands of people have signed a petition calling on the authorities to reverse a ban on supermarkets selling non-essential items during the lockdown there.
There the rules are similar to here, precluding supermarkets from selling non-essential items like electrical goods, telephones, clothes, toys and games, garden products and from dedicated sections for homewares.
But by yesterday afternoon, 17,000 people had signed a petition expressing opposition to the move.
And likewise here, any efforts to prevent some open outlets from selling certain goods, may not go down well among people already frustrated that they can’t shop as normal.
So expect efforts by the Government and retailer leaders to resolve the problem to continue.
Otherwise we could be facing something resembling a retail rebellion on both sides of the counter.