For Christians there is only one lord, Jesus (1 Cor.8:6). Yet the father is not Jesus but is lord (Rv.1:8), and John even called an angel lord (kurios: Rv.7:14): we might speak of Lord Kitchener as having been an earthly lord under the heavenly lord; the Sanhedrim and the Roman Empire were to be obeyed unless their lordship usurped God’s lordship. Jesus’ original audience (not us) were to call no one teacher (Mt.23:10), yet messiah has established teachers (Eph.4:11) for his born anew audience. Context decides when lord/teacher/father words are appropriate. Only God the father is in one sense, ontological, our father, yet Jesus, Paul, and John, could call there disciples their children, by implication themselves being their fathers – many others were similarly fathers (1 Jhn.2:13), arguably fitting the term presbuteroi (elders) of the spiritual maturity required to mentor. Indeed John implied himself to be a spiritual father in the same breath as speaking of Jesus being their advocate with the father (1 Jhn.2:1): a father under the father. Presumably John had no problems with a wooden approach to Mt.23:9, an approach perhaps coming from an over-reaction to a Roman Catholic use of the term father. In short, we’re talking about how father (patēr) was meant in Jesus’ egalitarian context of Mt.23:8-9, with perhaps overtones of necessarily being followed without question as highest authority. Jesus shot down the self-exalting attitude sprung up among Jewish teachers, and said “don’t join that set”. A Baptist minister can be more scribe & Pharisee than a Papal (papa) father, and we need to see even those who serve us as doing so under God to whom we have direct access.