| In Acta S. Apostolorum (1678) by John Lightfoot | | |
| In Evangelium Sancti Matthæi Horæ Hebraicæ et Talmudicæ (1658) by John Lightfoot | | |
| In Polycarpianam epistolarum Ignatianarum syllogen annotationes (1644) by James Ussher | | |
| In quibus, praeter Maccabaicam et Novi Testamenti historiam (1654) by James Ussher | | |
| Inaccessible glory. Or The impossibility of seeing Gods face, whilst we are in the body (1655) by Thomas Hodges | | |
| Independencie a great schsim proved against Dr. Owen his apology in his tract of schism (1657) by Daniel Cawdrey | | |
| Independency further proved to be a schism. Or, A survey of Dr Owens review of his tract of schism (1658) by Daniel Cawdrey | | |
| Institutio logicæ (1687) by John Wallis | | |
| Ioabs counsell and King Davids seasonable hearing it (1643) by William Bridge | | |
| Irenicum in quo casus (1654) by John Dury | | |
| Irenicum; or, An essay towards a brotherly peace & union, between those of the congregational and presbyterian way (1659) by Matthew Newcomen | | |
| Irenicum: to the lovers of truth and peace (1646) by Jeremiah Burroughs | | |
| Israels call to march out of Babylon unto Jerusalem (1646) by John Dury | | |
| Israels peace with God Beniamines overthrow (1642) by William Carter | | |
| Israels petition in time of trouble. A sermon preached in St. Margarets Church at Westminster (1642) by Edward Reynolds | | |
| Israels prayer in time of trouble, with Gods gracious ansvver therunto (1645) by Edward Reynolds | | |
| Israels tears for distressed Zion (1645) by John Wincop | | |
| Item, tractatus grammatico-physicus de loquela sive sonorum formatione (1688) by John Wallis | | |
| Jacobs seed: or The generation of seekers (1648) by Jeremiah Burroughs | | |
| Jacobs thankfulnesse to God, for Gods goodnesse to Iacob (1624) by Thomas Gataker | | |
| Jehojadahs iustice against Mattan, Baals priest: or The covenanters justice against idolaters (1645) by Joshua Hoyle | | |
| Jehoshaphats caveat to his judges (1644) by Thomas Case | | |
| Jerichoes dovvn-fall, as it was presented in a sermon preached in St. Margarets Westminster (1643) by Thomas Wilson | | |
| Jerusalems glory breaking forth into the world (1675) by Jeremiah Burroughs | | |
| Jerusalems watch-men, the Lords remembrancers (1643) by Matthew Newcomen | | |
| Jesus Christ Gods shepherd, and the man gods fellow, on Zach. 13. 7 (1658) by William Strong | | |
| Jews in America, or Probabilities, that those Indians are Judaical (1660) by Thomas Thorowgood | | |
| Johannis Wallis, S.T.D. Geometriæ Professoris Saviliani, in celeberrima academia Oxoniensi; atque Regalis Societatis Londini sodalis; Grammatica linguæ Anglicanæ (1674) by John Wallis | | |
| John Dury his petition to the Honourable House of Commons in England (1641) by John Dury | | |
| Joseph paralled by the present Parliament, in his sufferings and advancement (1646) by Francis Woodcock | | |
| Joy in the Lord: opened in a sermon preached at Pauls, May 6 (1655) by Edward Reynolds | | |
| Joy out-joyed: or, joy in overcoming evil spirits and evil men, overcome by better joy (1646) by Joseph Caryl | | |
| Judgements removed, vvhere judgement is executed (1644) by Anthony Burgess | | |
| Judgment and mercy: or, the plague of frogges inflicted, removed (1645) by Josias Shute | | |
| Judicium discretionis (1667) by Thomas Wilson | | |
| Just re-proposals to humble proposals (1650) by John Dury | | |
| Justification justified: or The doctrine of justification; briefly and clearly explained (1653) by Thomas Clendon | | |
| Katabaptistai kataptüstoi. The dippers dipt, or, the Anabaptists dvck’d and plvng’d over head and eares, at a disputation in Southwark. (1645) by Daniel Featley | | |
| King Charles his welcome home (1641) by John Bond | | |
| Large additions to the Practicall catechisme (1646) by Henry Hammond | | |
| Lettre du sieur Jean Dury touchant l’estat présent de la religion en Angleterre, Escosse et Irlande (1658) by John Dury | | |
| Lex talionis: or, God paying every man in his own coyn (1646) by Francis Woodcock | | |
| Light for smoke (1646) by John Ley | | |
| Light in darknesse (1648) by William Carter | | |
| Living loves betwixt Christ and dying Christians (1654) by Simeon Ashe | | |
| Living loves betwixt Christ and dying Christians; The second edition (1654) by Simeon Ashe | | |
| Logos autopistos, or, Scriptures self-evidence (1667) by Thomas Ford | | |
| Logou Alogia, seu, Exercitatio theologica de insipientiâ rationis humanæ, gratiâ Christi destitutæ, in rebus fidei. (1655) by Robert Crosse | | |
| Loiola Scena et Amsterodami (1648) by John Hacket | | |
| Lyford’s legacie; or, An help to young people (1656) by William Lyford | | |
