A goal-fest was hardly on the cards when this fixture was being considered, but the modest crowd had four goals to cheer before the break, and two possible penalties to debate.
Bray's new target man, Anto Flood, marked his home debut with an early strike, Gary McCabe signalled his return with a penalty and Aaron Greene netted with a fine header just before the interval.
Meantime, Harps - who were playing some nice ball when they got possession - had pulled one back with an opportunistic score by Ciarán O'Connor.
And more was to follow, O'Connor doubling his tally within minutes of the resumption, with McCabe following suit just inside the hour.
Just as fans were trying to remember the last time Bray had scored four in a League match, Dylan Connolly broke through and persisted in the face of substitute Harps keeper Harry Doherty's blocks, finally netting number five.
Ethan Boyle made a final scoring contribution when his fierce shot looped over Peter Cherrie's touch and fell into the net.
After a brief heavy shower had ensured the pitch would be as heavy as possible short of unplayable, Bray opened with threatening-looking movements.
It was the visitors, however, who had the first attacking opportunity, O'Connor giving notice of intent with a searching cross that found Caolan McAleer just offside.
Six minutes in, there was surprise that the referee was uninterested when Kevin Lynch upended former Bray man Seán Houston.
And still more when three minutes later, a dubious foul by Boyle on Connolly - who had already been fouled by Barry Molloy - attracted a free in a dangerous position.
McCabe stepped up and Hugh Douglas reached the ball, but his effort was blocked and Flood got to the loose ball before the defence and forced it home.
Two minutes later, a hand-ball by Keith Buckley gave Jonny Bonner a chance to respond, but his effort flew left of target.
Following another Connolly raid that ran out of steam, Harps worked well and when Conor Kenna's attempt to head away McAleer's cross fell short, O'Connor's first swing at it hit air, but he managed to recover and contrive a shot, though Cherrie saved well.
The visitors were astonished when Michael Funston's arm, dropped into the flight of Greene's cross, was adjudged deliberate, and ruled to have occurred within the area.
McCabe made no mistake from the spot, and Bray were suddenly two up.
Undaunted, O'Connor made a strong sally towards the Bray goal and found himself in a sandwich for his pains. Once more, no sanction followed, but Ciaran Coll was sent to the sideline to change his shirt and returned as No. 15.
Cherrie claimed a long punt out of defence by Boyle, and a McCabe free for a foul on Connolly was blocked, the follow-up being ruled out by the offside flag.
An ambitious aerial kick by Houston from an O'Connor cross flew high and to the left, and following the clearance Flood and Damien McNulty (who weren't exactly kissing cousins throughout) both needed attention after a clash.
Just after the half hour the Donegalmen had their strongest period so far, Douglas conceding a free in the corner with his challenge on O'Connor, and when Bonner's deadball came off the woodwork, O'Connor was well placed to stab it into Cherrie's net.
Flood suffered a couple of strong challenges, earning frees that came to nothing, and then tried a snap shot on goal himself from a cutback by John Sullivan, but Ciaran Gallagher made a fine reaction save.
And when a Greene shot was deflected over, McCabe's flagkick was headed out and back, with Lynch finding Kenna, and the captain finding Greene ready to find the net.
With only seconds to go to the break, a Harps corner taken by Bonner was only parried by Cherrie, and the Bray defence did well to clear the second attack.
Bray were surprised after the long ball that the referee failed to notice Boyle striong tug on Flood as he went forward, and Cherrie's eventual claim of a Harps free he initially fumbled brought the first half to a close.
If Bray had had the edge on the visitors so far, the scoreline nevertheless flattered them.
And Harps underlined that within minutes of the restart, O'Connor beating Kenna to a long ball out of defence and shooting hard. The advancing Cherrie got fingers to the rising ball - which might have risen to clear the bar if left - and while sending it high he also took enough out of it that it fell neatly behind him into the net.
It was no less than Finn Harps deserved, and they pressed hard forthe next ten minutes, earning a string of corners but failing to make use of them.
The attack fizzled out, though, after McAleer had belted a half-volley barely over the bar following a throw-in.
Then came further controversy: a long ball by Keith Buckley seemed about to land just outside the area, and Gallagher may have been concerned about a potentially unpredictable bounce.
For whatever reason, he dived low to head away as Connolly and Boyle were both approaching at speed, and one of them clipped him, Boyle performing a spectacular tumble-turn and roll before lying on the ground himself.
The action meanwhile, was continuing, and the loose ball had reached McCabe, who took a step and fed it to the net. Then, and only then, did the referee intervene, signalling both the goal and a stoppage for attention to the injured players.
Gallagher was unable to continue, and his place was taken very effectively by Doherty, who saved the visitors from several further goal-bound Bray shots in the half hour remaining.
Not all, though, for despite two rebuffs, Connolly managed at the third time of asking to bypass the goalie, who had stopped his first effort with his feet and parried his second, both time simply sending the ball back to the Bray winger.
Once more, Harps created a purple passge around the half-hour mark, and when substitute Paddy McCourt's free ricochetd off the wall and out for a corner, the former Derry man found Boyle with his set-piece and the defender didn't need an invitation to score.
With less than ten minutes left, Bray opened an flurry of attacks with a McCabe shot that Doherty managed to finger-tip over the bar, and followed with a series of corners, an off-target effort by Greene and a Connolly shot deflected onto the top of the net.
In the final minute of regulationtime, the referee blew a stoppage when Connolly was spotted on the ground, but he didn't need attention. Instead, he was soon sending another shot just right of the posts.
A Flood lob attempt finished on top of Doherty's net, and Bray ended the contest with a brace of corners taken by substitute Karl Moore.
And that four goals poser? In fact it's not been very long at all: the last home match of last season, against Cork.
Historically, Bray have scored four at least once most seasons, with 2004 a bumper year, featuring no fewer than five wins at four goals or more.
Colm Tresson got a hat-trick in a 6-0 rout in Oriel Park that year, and Eamon Zayed another in Athlone.
By Mícheál Ó hUanacháin
Bray Wanderers: 1 Peter Cherrie; 2 Hugh Douglas , 21 Tim Clancy, 4 Conor Kenna (c), 19 Kevin Lynch; 3 John Sullivan; 16 Dylan Connolly , 6 Keith Buckley, 11 Gary McCabe ; 9 Aaron Greene , 20 Anthony Flood