John P. Meier, «The Present State of the Third Quest for the Historical Jesus: Loss and Gain», Vol. 80 (1999) 459-487
Despite the questionable method and positions of the Jesus Seminar, the third quest for the historical Jesus has resulted in seven notable gains as compared with the old quests. (1) The third quest has an ecumenical and international character. (2) It clarifies the question of reliable sources. (3) It presents a more accurate picture of first-century Judaism. (4) It employs new insights from archaeology, philology, and sociology. (5) It clarifies the application of criteria of historicity. (6) It gives proper attention to the miracle tradition. (7) It takes the Jewishness of Jesus with utter seriousness.
the four canonical gospels are the only lengthy continuous sources for the historical Jesus that have come down to us. To be sure, the canonical gospels are permeated with the Easter-faith of the early church and must be carefully sifted with the criteria of historicity of which more anon. But when so sifted, they remain our main sources, if also our main problem. Moreover, I readily grant that Johns Gospel, the supreme example of systematic theology and high christology among the four gospels, presents special difficulties. Yet, in my opinion, nuggets of important factual information are preserved in John rather than the Synoptics. These nuggets include Jesus close connection with the circle of John the Baptists disciples before his own ministry began, his practice of baptizing followers during his ministry, his frequent trips to Jerusalem, the duration of his ministry over a number of years, the correct chronology of the Passion, and the non-Passover nature of the Last Supper. Certainly, the discourses in the Fourth Gospel are, in their present form, largely the product of the theology and perhaps the homilies of the Johannine community. But even here, individual logia can provide independent attestation of sayings also found in the Synoptics. John 12,25 on losing and keeping ones life (cf. Mark 8,35 parr.; Matt 10,39; Luke 9,24; 14,26) is a striking case in point.
As for the rest of the NT, the debate over the extent to which Jesus sayings (and a few facts about him) have been preserved in the Epistles, Acts, or Book of Revelation has been extensive and lively, though I tend toward a minimalistic view, feeling sure of only a few clear examples, mainly in Paul (1 Cor 7,10-11; 9,14; 11,23-26; see also Rom 1,3; 15,8; 1 Cor 15,3-5; also James 5,12; Heb 7,14; 5,7-8; Rev 3,3; 16,15). Outside the NT, while one may argue for the authenticity and independence of a few agrapha, the only significant independent source is Josephus Testimonium Flavianum in Book 18 of his Jewish Antiquities (18.3.3 §63-64). While debate continues over this passage, I am heartened by the fact that a number of recent scholars have basically accepted something like my suggested reconstruction of the authentic core text20.