He was known as Pàdraig Grannd nan Oran ("Peter Grant of the Songs"), which became a household name in the Highlands of Scotland for nearly fifty years.
Scottish scholar Donald Meek states that: "he was instrumental in forming what became the largest Baptist congregation in the Gaelic-speaking Highlands, but he was also at the forefront of itinerant evangelism throughout the area.
Professor Michael D. McMullen stated that "We have relatively few extant records from the early life of Baptists in Scotland, and Wilder's carefully presented collection of Grant's writings makes a very valuable contribution to the little that is available.
So far, however, we have not been privileged to sample the preaching style that proclaimed the Word of God, in both Gaelic and English, in the pulpit of Grantownon-Spey, and drew audiences from miles around.
Mr. Grant was in many respects a remarkable man, and we regret that we have not materials in our possession to enable us to give anything like a worthy record of his life.
By-and-by Mr. Grant was chosen pastor of the Baptist Church at Grantown, and he was spared to see the handful of people who then formed his charge increase under his own and his son's ministry to be a numerous and attached flock.
Mr. Grant was a genial, warm-hearted, and truly devout man, and Christians of all denominations greatly respected him, and unite in lamenting his loss.