Kautz, Christian Friedrich, baptized in Berlin, 1702, published in 1703 "Des 12 jährigen Jesu vom Nazareth Verstand im Fragen und antworten, darüber sich die juden verwundern," also "Erkannte Göttliche Wahrheit aus der Schrift Alten und Neuen Testamentes," Waldenburg, 1716, and a "Catechismus für Juden," 1720.
Keyper, a native of Prague, was Rabbi in Schleusinger, where he was converted and baptized by Superintendent Friedrich Ernest Weis in 1715. He afterwards was lecturer on Jewish antiquities in Altorf and in Regensburg. Later he gave lessons in Talmud and Rabbinics at Bremen. Wolff in Bib. Heb. 3, 4, N. 1356 b. speaks of him as a learned, upright and sincere man.
Kiel, a physician from Roumania, made, as a pious Jew a pilgrimage to Jerusalem, thinking that in the Holy City he would find spiritual satisfaction and peace, but he did not find it in the Judaism that he found there, but in the Gospel which was preached by the missionaries. He and his wife were baptized by Bishop Alexander in 1844, and he laboured afterwards as a medical missionary in Safed.
Klein, Julius Leopold, a native of Hungary, born at Nocskolez, 1810, died in Berlin, 1810. He was a physician, poet and writer. His works appeared in seven volumes, under the title "Dramatische werke," Leipsic, 1871-2.
Köbner, Pastor Julius, was born in Denmark in 1806. Was by profession an optician like Spinoza, but God vouchsafed to him greater spiritual sight than to the philosopher. He embraced Christian faith in the Lutheran Church of which he became a minister, but afterwards joined the Baptists. Endowed with spiritual and mental gifts, he henceforth laboured with great zeal in Copenhagen, where he built the Christian Chapel, and also in many other parts. Later he laboured in Berlin, where he died 1884. His notable writings are, "Das Lied von Gott," an epic poem from the creation to the redemption of the world. "Die Waldenser," a dramatic poem with notes, "Die Neue Erde." On his hundredth birthday, 1906, appeared a hundred of his choicest sermons in the press, under the title "Lebens Wasser."
Kofler, Carl, born in Lemberg, 1820, was baptized with his parents at Breslau in 1822, graduated at the University there, and was appointed Vicar in Bad Lardeck in Silesia in 1851. He is recorded to have been a gifted preacher of the Gospel and a conscientious pastor. He died in 1877.
Koppel, Dr. J., born in the Archduchy of Posen in 1830. He began to learn Hebrew when he was three years old. Afterwards he attended a Roman Catholic school, where he was badly treated, and he imbibed strong prejudices against Christianity. In 1846 he entered a Jewish seminary for teachers at Bromberg, and when he finished his studies, he was appointed teacher by the Government in a town near the Russian border, and also interpreter. At that time he realised that there was a great contrast between the Bible and the Talmud, but he had no inclination towards Christianity whatever. Coming to Berlin, he made the acquaintance of Dr. Jaffe, whose brother was a missionary of the British Society, and he advised him to go to him for Christian instruction. The result was that he was baptized by Jaffe. In 1860, Koppel entered the service of the British Society, and laboured at first in England. In Bristol he became acquainted with George Müller and with his institution, which served him to good purpose in his future activity. Returning the same year to Bromberg, it happened that one day a pair of boots were stolen from him, and a poor beggar boy was suspected of the theft. This incident awakened in Koppel's heart deep compassion towards the poor neglected boys, and he applied to the municipal authorities for permission to found a Home or Ragged School for them where they might receive Christian training. This permission was, after some hesitation, granted, and the Home was opened in 1864, which served at the same time as a refuge for gutter children, orphans, Jewish enquirers and converts. Koppel then displayed great activity together with Dr. Ben Zion, Dr. Mossa and other friends whom he gathered around him. They instructed the children, visited the prisons, preached to the Jews, of whom thirty-five were converted there. Koppel laboured in faith, and the means of support were not wanting. A waiter sent him 200 thaler and rich people helped him liberally. In 1866 there were seventy inmates in the "Home" at Salem. In 1869 Koppel, not feeling strong enough to carry on the work, delivered it to others and went to London, where he did similar work and was well known at the Mildmay Conference Hall. Subsequently he went to Texas to found a colony there.
Kronheim, Joseph Nathaniel, a native of Magdeburg and son of wealthy parents. In his youth he led a restless life, served as a soldier under Napoleon I. in his Russian campaign, and then was schoolmaster in Magdeburg, where he bought a New Testament, to teach moral principles from it. The rabbi, on hearing of this, dissolved the school. He then came to England and made the acquaintance of Bishop Alexander, who preached the Gospel to him. He then took more time to investigate the question at issue between Judaism and Christianity, travelling in the country to sell optical instruments, till he came to the Rev. Wyndham Madden, of Woodhouse Parsonage, near Huddersfield, by whom he was further instructed and baptized in 1832. In 1835 he settled as optician in Belfast. A year later the friends of the Jews there, observing his Christian character, ability, and great Biblical knowledge, asked him to give up his business and become an agent of the Belfast Auxiliary Society, which he did, though he was then sixty years old. Through him a lively interest was awakened in Ireland for the cause of missions among the Jews. He laboured there for seventeen years, and died in 1852.
Krönig, Rev. Joshua Charles Solomon, heard the Gospel in Paris from the L.J.S. missionary Markheim, and was baptized by him in 1857, in the chapel of Lewis Way, when Lord Shaftesbury was one of the sponsors. After doing good work in London as a city missionary, he studied theology at King's College, was ordained by the Archbishop of York, 1871-1872, and was appointed by trustees to the Vicarage of St. Barnabas, Hull, where he laboured for the rest of his life as a faithful minister of the Gospel to his congregation and missionary to his own people, esteemed and beloved by them both. In 1875 he opened a reading-room for Jews, which he called a "Beth hamedrash," in which he placed one of his own converts as house-father. In 1881 he bought a house for this purpose, on which he placed the inscription, "The doors of Zion, house for studying God's Word." In 1884, he told a pathetic story of a Jew who was a blasphemer, but whom the power of the Gospel converted and regenerated, so that he became his assistant in the work of the mission. Krönig was much sought after as a deputation.
Kropveld, Rev. E., Pastor at Ablasserdam in Holland and Secretary of the Dutch Reformed Church Mission to the Jews. He was brought up in strict Jewish orthodoxy. Starting in life in a merchant's office and living carelessly, he one day had a conversation with a Christian peasant, who assured him that he was certain of entering at last into the heavenly Canaan. This made a deep impression upon him, and he began to live in stricter conformity with Judaism. At the age of seventeen he heard the L.J.S. missionary Pauli preach, and felt the power of the Gospel message, which led to his being baptized. He then became a colporteur of religious books, when he suffered much from his friends, yet lived so economically that he managed to save sufficient money to enable him to study for the ministry. He then became Pastor in Rundem, Minnertsga, and at last in Ablasserdam. He wrote several books in relation to the Jews.