A dignitary of the Roman Church and counsellor of the pope.
By the term cardinal (Cardinalis) was originally understood every priest permanently attached to a church, every clericus, either intitulatus or incardinatus. [C. 3 (Gelasius I, 492-496), D. XXIV. C 35 (Gregory I, 595), D. LXXXI. C. 6 (Gregory I, 603), D. LXXIV. C. 42 (Gregory I, 592), C. VIII, q. 1.] It became the usual designation of every priest belonging to a central or episcopal church, an ecclesiastical cardo (Lat. for hinge). Cf. Hincmar of Reims, "De jure metropolitani", c. 20 (Opp. ed. Sirmond, II, 731); C. 2, §6 (Pseudo-Isidore), D. XXII. Lastly it was equivalent to principalis, i. e., excellent, superior, and is so used by St. Augustine (De baptismo, I, 6; ed. Bened. IX, 56).
The origin, development, and modifications of this office will be treated as follows: I. Cardinal-priests; II. Cardinal-deacons; III. Cardinal-bishops; IV. Cardinalitial dioceses, titles, and deaconries; V. Relations of the cardinals to the bishops; VI. Relations of the cardinals to the pope; VII. Nomination of cardinals; VIII. Duties of cardinals; IX. Rights of cardinals; X. The College of cardinals.
I. CARDINAL-PRIESTS
Until late in the Middle Ages the title of cardinal was given to prominent priests of important churches, e.g., at Constantinople, Milan, Ravenna, Naples, Sens, Trier, Magdeburg, and Cologne (cf. G. Phillips, Kirchenrecht, Ratisbon, 1845 sq., VI, 41 sqq.; P. Hinschius, "Das Kirchenrecht der Katholiken und Protestanten in Deutschland", Berlin, 1869, I, 318 sqq.). In keeping with this custom we find the term Cardinalis applied at Rome from the end of the fifth century to priests permanently attached to the (twenty-five to twenty-eight) Roman tituli, or quasi-parishes (quasi diœceses), belonging to the church of the Bishop of Rome, the pope-therefore to the Cardo ecclesia par excellence-in which tituli the Sacraments of Baptism and Penance were administered, and which were also often called tituli cardinales. The "Liber Pontificalis" describes as follows this quasi-parochial system of ancient Rome: "Hic [Euaristus, 99-107?] titulos in urbe Româ divisit presbyteris …"; and again: "Hic [Dionysius, 259-268] presbyteris ecclesias dedit et cymeteria et paroccias diocesis constituit"; and elsewhere: "[Marcellus, 308-309] XXV titulos in urbe Româ constituit quasi diocesis propter baptismum et pœnitentiam multorum qui convertebantur ex paganis et propter sepulturas martyrum" (op cit., ed. Duchesne, Paris, 1886, I, 126, 157, 164). In other words, an ecclesiastical division of the city for various parochial purposes is attributed to popes of the second and third centuries. Such a division, scarcely possible in the period of persecution, is vouched for at the end of the fifth century by the signatures of Roman presbyters present at the Council of Rome in 499 under Pope Symmachus (cf. A. Thiel, Epistolæ Romanorum Pontificum genuinæ, Brunsberg, 1868, 651 sqq.). These presbyters were thenceforth known as cardinales [C. 5. (Constitutum apocryphum Silvestri I, about the end of the fifth century, c. 7), D. XCIII, C. 2 (Concilium apocryphum Silvestri I, about the end of the fifth century), C. II, q. 4; C. 3, 4, 5 (Roman Synod under Pope Stephen III, 760), D. LXXXIX; Letter of Leo IX (1053) to Michael Cærularius in Jaffé, "Regesta Pontificum Romanorum", 2d ed. (Leipzig, 1885), no. 4302].