What I find interesting is how a study of the textual traditions contribute to our understanding of the relationship between Christians and Jews/Judaism in the early centuries. Two examples come to mind:
1. Rom. 15.8. This verse reads: "For I declare that Christ became a servant of the "circumcision" for the sake of God's truth". Robert Jewett (Romans, 886) notes that the perfect verb gegenēsthai is replaced by the aorist genesthai in B C* F G Ψ 630 1739 1881 etc. In Jewett's view this change to the aorist is secondary and "serves to drop the implication of the original reading that Christ remains the servant of the Jews".
2. Matt. 8.4. This verse reads: "Go, show yourself to the priest and the present the offering that Moses commanded, as a testimony to them". But the Diatessaron(eph), Ishodad of Merv, Romanos, the Liege Harmony, and the Venetian Harmony, read: "Go, show yourself to the priest and fulfill the law". This reading arguably stems from a Judeao-Christian background that is perhaps more concerned with a closer relationship between Christians and the Torah (Cited from Craig Allert, A High View of Scripture, 118).