[q. v.] and Lewis du Moulin [q. v.], but attached himself next year to John Goodwin [q. v.] the independent. He joined a religious society of apprentices, and became (1638) a member of the separatist congregation gathered in Southwark by Henry Jacob (1563–1624) [q. v.], and then ministered to by John Lathrop [q. v.] Kiffin preached occasionally. In 1641-2, during the ministry of Henry Jessey [q. v.], he and others became baptists, but remained a member of Jessey's church till 1644 (Gould, Baptists of Norwich, 1860, pp. cxxviii et sqq.) Early in 1641 he was arrested at a Southwark conventicle and committed by Judge Mallet to the White Lion prison, bail being refused. Mallet was himself committed to the Tower in the following July, whereupon Kiffin obtained his release. On 17 Oct. 1642 he was one of four baptist disputants encountered at Southwark by Daniel Featley [q. v.]
In 1643 Kiffin began business in woollen cloth on his own account with Holland. He became rich. In 1647 he was parliamentary assessor of taxes for Middlesex. In 1649 he made good use of the five weeks' grace before the coming into force of restrictions upon the import of foreign goods. In 1652, on the outbreak of the Dutch war, he gained money and privileges by furnishing requisites for the English fleet. Meanwhile he was pursuing his religious labours. His name heads in 1644 the signatories to a confession of faith drawn up by seven churches 'commonly (but uniustly) called anabaptists.' Joshua Ricraft, a presbyterian merchant, attacked him (1646) as 'the grand ringleader' of the baptists. Thomas Edwards (1599–1647) [q. v.] assailed him in 1646 as a 'mountebank,' and as adopting the 'atheistical' practice of unction for this recovery of the sick (Gangræna, iii. 19). Kiffin had offered in vain (15 Nov. 1644) to discuss matters publicly with Edwards in his church (St. Botolph's, Aldgate). He joined Hanserd Knollys [q. v.] in a public disputation (1646) at Trinity Church, Coventry, with John Bryan, D.D. [q. v.], and Obadiah Grew, D.D. [q. v.] In January 1649 parliament, in response to a petition from Ipswich, gave him liberty to preach in any part of Suffolk, where he travelled with Thomas Patience, his assistant. He corresponded (1653) with the baptist churches in Ireland and Wales. His settlement with the congregation, which, on 1 March 1667, opened a meeting-house in Meeting-house Yard, Devonshire Square, London, is usually dated in 1653. But as early as 1643 Kiffin and Patience ministered to this congregation, which consisted of seceders from Wapping practising close communion, He signed the declaration of 1651. On 12 July 1655 Kiffin was brought before Christopher Pack, the lord mayor, for preaching that infant baptism was unlawful, a heresy visited with severe penalties under the 'draconick ordinance' of 1648. The execution of the penalty was indefinitely postponed. A pamphlet ('The Spirit of Persecution again Broke Loose,' &c., 1655, 4to) contrasts this leniency with the severity used towards John Biddle [q. v.] He was M.P. for Middlesex, 1656-8.
Between 1654 and 1659 Kiffin is spoken of as captain and lieutenant-colonel in the London militia. This may account for his arrest, and the seizure of arms at his house in Little Moorfields, shortly before the Restoration, in 1660, by order of Monck, who was quartered near him. He was released by order of the common council, and the arms were restored to him. A more serious trouble befell him later in the year. A forged letter, dated 21 Dec. 1660, and professing to come from Taunton, implicated him in an alleged plot, following the death of the Princess of Orange (24 Dec.) He was arrested on 29 Dec., and kept in the guard-house at Whitehall, but released on 31 Dec. by Sir Robert Foster [q. v.], the chief justice, the date and other circumstances proving the letter a forgery. On 7 Jan. 1661 Venner's insurrection broke out. Kiffin at once headed a 'protestation' of London baptists, but nevertheless was arrested at his meeting-house and detained in prison for four days.
About 1663 he gave evidence before a committee of the House of Commons, and before the privy council, against granting to the 'Hamburg Company' a monopoly of the woollen trade with Holland and Germany. His evidence permanently impressed Charles II in his favour, and gained him the goodwill of Clarendon. A year later he was arrested at the instance of George Villiers, second duke of Buckingham [q. v.], on suspicionof being concerned in an anabaptist plot against the king's life. He wrote to Clarendon, and was at once released by the privy council, and though a prosecution was threatened nothing came of it. In 1669 his meeting-house was in Finsbury Court, Moorfields. On two occasions, in 1670 and 1682, Kiffin, when prosecuted for conventicle-keeping, successfully pleaded technical flaws. On two other occasions (one in 1673) he obtained interviews with the king, securing the suppression of a libel against baptists, and the pardon of twelve Aylesbury baptists who had been sentenced to death under 35 Eliz. c. 1. Crosby relates that Charles wanted a loan of 40,000l. from Kiffin, who made him a present of 10,000l., and said afterwards that he had thus saved 30,000l. In 1675 he took part
