This is some more from Highways & Byways on The Borders:
There are still to be seen wishing the burgh the ruins of the Cross Church and of the Church of St Andrew. The former got its name from the fact that in May 1261 “a magnificent and venerable cross was found at Peblis”, which was supposed to have been buries close on a thousand years before that date. Shortly after the unearthing of this cross, there was found near the same spot a stone urn, containing ashes and human bones, and on a stone the words cried: “The place of St Nicholas the Bishop.” On account of the miracles which were reputed to have been wrought where the cross was discovered,
Alexander III caused a church to be erected on the spot “in honour of God, and of the Holy ‘rood”. This Cross Church in some unexplained was escaped practically unscathed during the English invasion of 1548-49 and from 1560 till 1784 it served as aa Parish Church – deprived, no doubt, of many an interesting relic of the past. At the last date, our zealous forefathers… pulled it down – all but a fragment – in order out of the material so obtained, to build a new Parish Church. (They had in those times a perfect genius for wrecking the beautiful and interesting and for erecting the ugly and the dull.)
The other old church, that of St Andrew, was founded about the year 1195. It, however, unlike its neighbour suffered badly at the hands of the English in 1548 after which it gradually fell into ruin, and met the fate that was wont to wait on most of our venerable Scottish buildings. The tower alone remained, impervious to wind and weather, defiant of man’s destroying hand. … it was in the church of St Andrew, tradition says, that Cromwell’s troopers stabled their horses in 1650 when siege was being laid to Neidpath Castle.
This is interesting as it suggests the iconoclasm was not general, but aimed at named saints rather than the cross per se, hence The first church was largely unscathed by the English. It also points to the links, or carry over of the Roman pagan beliefs into the early Christians, echoing the notion of early Christians grafting onto pagan roots. Or theft and vandalism, as some might prefer.