To be a believer, then as later, meant believing what the apostles taught. It is in this sense that apostolic succession is a New Testament truth. Believers succeed the apostles as they accept what the apostles taught. It is this succession not of ecclesiastical power as the Church of Rome teaches but of doctrine. This is why the apostles not only framed the Christian faith in doctrinal terms but called for its preservation and protection in this form. There is no Christian faith in the absence of " sound doctrine"(1 Tim.1;10; Tit.1:9),"sound instruction" (1 Tim.6:3),or pattern of sound teaching" (2 Tim.1:13-14). It is this doctrine, or more precisely, the truth it contains and expresses, that was "taught" by the apostles and "delivered" to the Church. It is this the message that is our only ground for hope (Tit.1:9) and salvation(1 Cor.15:2;1 Peter 1:23-25). Without it, we have neither the Father nor the Son (2 John 2:9). Indeed Paul says we can grow in Christ only as we stay within this doctrinal framework, for its truth provides the means for our growth (Col. 2:6). It is no wonder that Christians are urged not to depart from the apostlic teaching they received "in the beginning" (John 2:7,24,26; 3:11) or they had heard ( Heb.2:1), for it is the "faith once for all entrusted to the saints" (Jude 3).
~David Wells No Place For Truth Or Whatever Happened to Evangelical Theology?