Alexander, an eminent Catholic divine, was born in 1737 at Ruthven, in Banffshire, in the north of Scotland. His parents were of humble rank, and unable out of their own resources to educate their son. The kindness of a rich neighbour supplied the means; and young Geddes, after a seven years' course at the Roman Catholic seminary of Scalan, was sent to the Scottish College at Paris, where he made great progress in theology, and mastered the most important of the modern tongues. On his return to Scotland he became private chaplain to Lord Traquair, a Catholic nobleman in Peeblesshire, and in 1769 priest to the congregation of Auchinhalrig in his native county. He here gained a very strong hold over the affections of his people, by the completeness of his self-devotion to their welfare. Now it was that the idea of a new translation of the Bible adapted for the Catholics of England occurred to him; but during his whole stay at Auchinhalrig, his straitened means prevented him from procuring the needful books. In 1779 he went to settle in London, with a view to carrying out this design, taking with him the good opinion of his people, and the degree of LL.D. from the university of Aberdeen, which, since the Reformation, had never bestowed a similar honour on any Catholic. He had there the good fortune to make the acquaintance of Lord Petre, who supplied him with the necessary books, and a handsome allowance till his task should be completed. With this assistance he began his work; and in 1780 published a prospectus of it, which bore that the Vulgate was to be the basis of the new version. Finding, however, that the Vulgate was in many places inaccurate, he changed his plan, and resolved to translate directly from the Hebrew and Greek originals. Everything that hard toil could do to make this great undertaking as complete as possible was done; and in 1786 Geddes published a prospectus of his new plan, with a specimen of the work, and afterwards a "General Answer to the Queries, Counsels, and Criticisms" which these called forth. Despite his indefatigable exertions, he was not able to publish the results of his labours till the year 1792, when he gave to the world the first volume of his version under the title of "The Holy Bible, or the Books accounted sacred by the Jews and Christians, otherwise called the Books of the Old and New Covenants, faithfully translated from corrected texts of the originals, with various readings, explanatory notes, and critical remarks." Next year appeared the second volume, which brought down the work to the end of the historical books; and in 1800 the third, which contained his critique on the Pentateuch. This was the last volume that he was destined to publish. In 1802, while engaged on a translation of the Psalms, he was cut off rather suddenly in the sixty-fifth year of his age. His version of the Psalms, which he completed as far as the 118th, was published in 1807.

Geddes's theological opinions were on many points so different from those then current in England, that for some time he stood quite alone, an object of equal alarm and hostility to his own church and all the Protestant denominations. The former, indeed, set the example of the persecution, to which he was for a considerable period subjected. His independence of thought and action was the cause of his leaving Auchinhalrig; and after he published his version of the Bible, a majority of the Catholic bishops in England forbade its use in their sees, while the apostolic vicar of the London district interdicted him from officiating as priest. This is hardly to be wondered at, as Geddes denied not only many of the tenets of the Romish Church, but even the authority of the pope. He denied the inspiration of the Scriptures, the divine legation of Moses (whose miracles he either rejected altogether, or tried to explain away according to natural laws), and pronounced the Mosaic account of the creation "A most beautiful mythos or philosophical fiction, contrived with great wisdom, and dressed up in the garb of real history." This view will be seen at a glance to identify Geddes with the school of German Rationalists, the leaders of which, Paulus and Eichhorn, were his personal friends. It is no wonder that accusations of infidelity, and an ill-masked desire to destroy the authority of Scripture, were heaped upon him from all quarters. To dissipate these charges, he published an "Address," in which he proclaimed himself "a sincere though unworthy disciple of Christ," and denounced those as the real enemies of religion "who seek to support her on rotten props, which moulder away at the first touch of reason and leave the fabric in the dust." Despite these assurances, however, Geddes continued to be looked upon as a dangerous champion of infidelity; and his works, if they did nothing more, at least directed the thoughts of men to establishing the principles of Christianity on a surer basis than before. The credit refused to his honesty and ability at home was readily conceded by his German friends, Paulus and Eichhorn, the latter of whom declared Geddes to be the only English theological writer of that day by whose opinion he would consent to be judged. The foregoing facts have been taken from the "Life of Geddes," by Dr Mason Good, London, 1803. The biographer gives a very detailed list, with specimens of Geddes's compositions in all the languages with which he was acquainted, and a full analysis of his translation of the Bible. This work he criticises as "for the most part plain and perspicuous, conveying the sense of the original in its native simplicity. But his language is occasionally unequal, and strongly partakes of the alternations of his own physical constitution; in consequence of which, in the midst of a passage most exquisitely rendered in the main, we are at times surprised with scholastic and extraneous expressions, or disgusted with intolerable vulgarisms." The "Life of Geddes" also contains some interesting specimens of the Latin correspondence carried on for many years between the Scottish philosopher and his most eminent friends and fellow-labourers in the same field in Germany.