John, generally distinguished as "The Essayist," was born in the parish of Halifax, Yorkshire, Sept. 17, 1770. His parents occupied a small farm-house between Wainsgate and Hebden-bridge, and maintained themselves partly by farming and partly by weaving. They were persons of earnest piety, and of strong intelligence, though of limited cultivation, with little book-knowledge except such as they obtained from some ponderous volumes of Puritan theology. They married rather late in life: John was their first-born, and they had no other child besides his brother Thomas, who was four years younger—circumstances not favourable to the development of the social qualities. From childhood his character was marked by a sharply-defined individuality. To use his own expressive language, he felt "as if dissociated from the whole creation," and recoiled from human beings into a cold interior retirement. His outward life was marked by timidity and "infinite shyness;" his interior life was crowded and agitated with incommunicable feelings. His antipathies were strong, though not malicious, and his associations intensely vivid. For a number of years he would not sit on a stool which belonged to a man who died in a sudden and strange way, and whose ghost was said to have appeared in a barn near his house. His emotions were strongly roused by passages in favourite authors, such as Young's Night Thoughts. Single words (as chalcedony or hermit) or the names of ancient heroes had a mighty fascination for him. But while he felt isolated and shut out from human sympathy, he found relief and exquisite delight in the contemplation of natural scenery. "Sweet nature!" he exclaimed many years after, "I have communed with her with inexpressible luxury." A flower, a tree, a bird, a fly, was enough to kindle a delightful train of ideas and emotions, and sometimes to elevate the mind to sublime conceptions. Yet, in very early life, the great interested him more than the beautiful. Great rocks, vast trees and forests, emphatically dreary, caverns, volcanos, cataracts, and tempests, were, in reading and fancy, the objects of his highest enthusiasm; and in the contemplation of human character he preferred the bold and the heroic. Filled with restless thoughts and aspirations, he felt as a foreigner in his native place, and some of his earliest musings were on plans for leaving it. The dull monotonous occupation of weaving, in which he assisted his parents, and the utter want of sympathy in those around him, increased his disgust with his position. He performed the tasks assigned him with evident signs of repugnance, and in a manner which showed little aptitude for them; yet his general conduct was exemplary, reverential to his parents, and very free from any marked irregularity.

As a compensation for much that was undesirable in his social relations, the moral and religious influences he was under were powerful and salutary. His impressions of religion assumed as early as his fourteenth year a decided form. Just after the completion of his seventeenth year he joined the religious society of which his parents were members—that of the Baptist denomination—at Wainsgate. Their pastor was Dr John Fawcett, a man venerable for his piety, with talents devoid of brilliancy but assiduously cultivated, and who combined with a puritanic theology an extensive acquaintance with English literature (including works of fiction), which placed him, in point of mental cultivation, far ahead of his co-religionists in Yorkshire and the neighbouring districts. For many years Dr Fawcett conducted a flourishing seminary at Brearley Hall, which was subsequently carried on by his son at Ewood Hall. With him young Foster was placed for the purposes of general education and of preparation for the ministerial office, in accordance with his own inclination and the wishes of his friends, who had some perception of his mental superiority. Part of each day was still spent in his customary employments at home; but, to make up for this interruption of his studies whole nights were frequently devoted to reading and meditation, sub die, in his preceptor's garden. His school exercises were accomplished slowly and laboriously, which was the case with all his literary performances. At Brearley he had access to a large and miscellaneous library; he was most interested with voyages and travels, and these constituted throughout life his favourite reading. On leaving Brearley he proceeded to the Baptist college at Bristol, at that time (1791) and for some years later the only theological institution belonging to that denomination. The Rev. Joseph Hughes, the originator and dissenting secretary of the Bible Society, was then the classical tutor, having succeeded Robert Hall, who had just removed to Cambridge. Foster remained only a twelvemonth at Bristol, and, if his own statement be taken as correct, without much improvement in scholarship; but during that period he gained the friendship of Hughes, visited Hannah More and her sisters at Cowslip Green, and listened for the first time to the eloquence of Hall. On leaving Bristol he spent three months at Newcastle-on-Tyne, where he preached to a very small audience, and whiled away his leisure time in desultory musings, conscious of possessing superior powers, but neither happily combined nor fully brought out. After visiting his Yorkshire friends he went to Ireland, where he spent little more than a year, in Dublin, first as a preacher, and then as a schoolmaster, but failed to establish himself in either capacity. Early in 1797 he became the minister of a general Baptist church at Chichester; here he remained for two years and a half, and though his religious earnestness increased, it produced little effect on his hearers. We next find him at Battersea, visiting his friend Hughes, and instructing twenty-one young Africans brought over by Zachary Macaulay from Sierra Leone. In 1800 he removed to Downend, a village five miles from Bristol, and preached alternately in a small chapel there, and in another at Fishponds belonging to a lunatic asylum then under the management of Dr Joseph Mason Cox, whose brother-in-law he afterwards became. In 1804, on the recommendation of Robert Hall, who described him as "a young man of the most original and extraordinary genius, of unexceptionable character, and of the most amiable temper," he became minister of a congregation at Frome. The characteristics of his preaching at this period have been traced with great fidelity by his friend (and constant hearer) Mr Sheppard. "The sermons of Foster," he remarks, "were of a cast quite distinct from what is commonly called oratory, and indeed from what many seem to account the highest style of eloquence, namely, a flow of facile thoughts through the smooth channels of uniformly elevated polished diction, graced by the utmost appliances of voice and gesture. They were distinguished by an unambitious and homely sort of loftiness, which displayed neither phrase nor speaker, but things, while the brief word and simple tone brought out the sublime conception 'in its clearness' by a fund of varied associations and images, by graphic master-strokes, the frequent hints of profound suggestion for after meditation, by cogent though calm expostulations and appeals, and by shrewd trains of half-latent irony against irreligion and folly, in which, without any descent from seriousness and even solemnity, the speaker moved a smile by his unconscious approach to the edge of wit, yet effectually quelled it by the unbroken gravity of his tone and purpose."

After two years a swelling in the thyroid gland, which constant public speaking, and even much talking in company, tended to aggravate, obliged Mr Foster to resign his charge at Frome. He had also a growing conviction that the press, and not the pulpit, was the chief medium through which he could efficiently employ the talents committed to his trust. For some time, evidently with a view to authorship, he had committed to paper observations on natural objects, illustrations of human character, and reflections on morals and religion, in an aphoristic form. Many of these contain the germ, and even the exact phrasology, of passages to be found in his published writings. During his residence at Frome he wrote and published the Essays, which at once established his reputation "as (to use Sir James Mackintosh's language) one of the most profound and eloquent writers that England has produced." Within little more than a twelvemonth they passed through three editions; the eighteenth appeared in 1845, and since that time their circulation has been unabated. Multitudes of young persons have regarded as a bright era in their mental history the hour when this volume first came into their hands, and have never ceased to rejoice in its stimulating and elevating influence on their faculties. It has been to them a dayspring revealing a world of living beauty and wonders where all was before involved in deathlike torpor and gloom. Its intellectual power and deep-toned eloquence has dissolved in many minds the unhappy and absurd association of piety with mental weakness and vulgarity; while, on the other hand, it has released from their trammels not a few who had been wont to regard general literature and freedom of thought as the exclusive property of the profane.

The last of the four essays, On some of the Causes by which Evangelical Religion has been rendered unacceptable to Persons of Cultivated taste, has probably contributed more than anything else to that reformation in style which is perceptible in our modern religious literature, and of which Foster himself in his posthumous lectures has given so many beautiful specimens.

Before leaving Frome, Foster commenced writing in the Eclectic Review, and for the next twelve years contributed from ten to above twenty articles annually. In May 1808 he married the lady to whom his Essays were originally addressed in an epistolary form, and with whom his acquaintance had commenced seven years before at Battersea. Her mother and two of her sisters resided at Bourton-on-the-water, a retired, respectable village in Gloucestershire. To this place he removed on his marriage, which proved an eminently happy one. Here he led a very secluded life, writing reviews during the week, and on Sundays preaching in the neighbouring villages; the latter employment he valued as aiding his own piety, and keeping up an acquaintance with mankind. While at Bourton he lost both his parents, and became the father of five children, two of whom died in infancy. In 1817 he returned to Downend, where he wrote his Essay on the Evils of Popular Ignorance, in which he warmly urges the necessity of a national system of education, and portrays with appalling truthfulness the barbarism existing in our masses; a repulsive spectacle, which he terms "a gloomy monotony: death without his dance." Having relinquished his ministerial office at Downend, and removed to the neighbouring village of Stapleton, about two miles from Bristol, he delivered a series of discourses at Broadmead chapel, which were well attended by persons of almost all denominations. On Robert Hall's settlement in Bristol, he declined to continue this service, saying, "Now Jupiter is come, I can try it no more." Most of these discourses were published soon after his decease, and have lately been reprinted by Mr Bohn in his Standard Library. In 1826 his only son, an amiable, thoughtful youth, died of consumption. Six years later he was deprived of his estimable wife, to whom he felt himself indebted not only for a very great portion of happiness, but for whatever mental improvement he had made during their married life, a period of five and twenty years. Her intellect was remarkably strong and correct, and in refinement of perception and depth of reflective feeling she had few equals. This event deepened his constitutional pensiveness, and prompted him to indulge more than ever in those intense musings on the state after death, "the secrets of the invisible world," which form an ever-recurring topic in his correspondence. In addition to this greatest loss, he found himself, by the deaths of Hall, Hughes, and others, standing almost alone, bereft of the companions of his youth and mature life. His latter days were, however, soothed by the affectionate attentions of his two daughters who resided with him. After languishing for some weeks in a state of devout preparation for the final event to which he looked forward with a calm dignity and a childlike humility that were most impressive, he expired quietly and (as he wished) alone, October 15, 1843.

Besides the works already mentioned, Foster published a Discourse on Missions in 1818; an Introductory Essay to Doddridge's Rise and Progress of Religion (since reprinted separately) in 1825; and Observations on Mr Hall's Character as a Preacher, appended to Dr Gregory's Memoir in the collected edition of Hall's Works, 1832. He also wrote An Introduction to a pamphlet by Dr Marshman in vindication of the Serampore Missionaries. He was the author (anonymously) of Two Letters on the Established Church, addressed to the editor of the Morning Chronicle; and of Five Letters (in the same journal) on the Ballot, of which he was a strenuous advocate; these and Nine Letters of Religious Advice and Consolation to an interesting young person (the niece of his friend Mr Cottle) in her last illness, will be found in his Life and Correspondence, 2 vols., the third edition of which has lately appeared in Bohn's Standard Library.

His contributions to the Eclectic Review amounted to 185 articles, of which Dr Price published a selection, containing 59 papers, in 1844.