Once Robetrt Brucewas ready for the ministry, Andrew Melville, understanding how the Lord moved through him, brought him over to the General Assembly, in 1587, and persuaded the Church of Edinburgh to call him to a position there, in the place of James Lawson, the successor of John Knox. It should be remembered that Bruce was now 33 years old, which was much older than someone normally coming into the ministry.
He could not, however, be persuaded to take the position (although he was willing to work there for a time), until, by the joint advice of the ministers of the city, and the following ruse, he was, as it were, trapped into it. At a time when the sacrament was to be dispensed at Edinburgh, one of the ministers asked Bruce, who was to preach in the afternoon, to sit by him; and after having served Communion to two or three tables, he went out of the church, as if he had been to return in a short while; but instead of this, he sent notice to Bruce, that unless he continued with the Communion, the work would stop. Bruce, thinking that the minister had been seized suddenly with some kind of sickness, and the eyes of all the people being fixed on him, many entreating him to supply the minister’s place, proceeded to the administration of the Communion, and that with such emotion amongst the people, the like that had never before been seen in that place. When he was later urged by the rest of his brethren to receive, in the ordinary way, ordination by the laying on of hands, he refused; because he already had the material part of ordination, viz., the call of the people, and the approbation of the ministry; and besides, he had already celebrated the sacrament of the supper, which was not by a new ordination to be made void. So, having tried the work, and finding the blessing of God on it, he accepted the position and was from that time principal actor in the affairs of the Church, and a constant and strenuous maintainer of the established doctrine and discipline thereof. While he was a minister at Edinburgh, he shone as a great light through all these parts of the land. James Melville in his diary writes, ‘The ministry of Mr Robert Bruce was very profitable and mighty that year (1588), and divers years following most comfortable to the good and godly, and most fearful to the enemies.’ Another wrote, ‘The nobility respected him for his birth and connections; his eminent gifts as a preacher gained him the affections of the common people, and those who could not love him stood in awe of his commanding talents, of his severe and incorruptible virtue.’ The power and efficacious energy of the Spirit accompanied the word preached by him in a most sensible manner, so that he was a terror to evil doers, the authority of God appearing with him; in that he forced fear and respect even from the greatest in the land. Even the young James VI himself, and his Court, thought so highly of him that when he went to Denmark to bring home his wife in October 1589, he expressly desired Robert Bruce to acquaint himself with the affairs of the country and the proceedings of the Privy Council, professing that he depended more in him than the rest of his brethren, or even all his nobles. And, indeed, in this his hopes were not disappointed; for the country was quieter during his absence than either before or after his return; in gratitude for which, Bruce received a congratulatory letter, dated February 19, 1590, in which James acknowledged, that he would be obligated to him all his life for the pains he had taken in his absence to keep his subjects in good order. James did not return home with his bride until May 1590, so Bruce’s held his position in the Privy Council for around seven months. It is well known that the king had such esteem for Bruce, that upon a certain time, before many witnesses, he gave him this testimony, that he judged him worthy of a quarter of his kingdom; but in this, as in others of his great promises, he proved no slave to his word; for not many years after he obliged this good man, for his faithfulness, to leave the kingdom. Probably as a result of his family seeing the favour he had, his parents reconciled with him, and returned his lands.