John was primarily concerned with demonstrating that Jesus is the Son of God (John 20:31), and he uses monogenes to highlight Jesus as uniquely God's Son—sharing the same divine nature as God—as opposed to believers who are God's sons and daughters by adoption (Ephesians 1:5). Jesus is God’s “one and only” Son.
Ang pangunahing layunin ni Juan ay ipakilala si Hesus bilang Anak ng Diyos (Juan 20:31), at ginamit Niya ang salitang bugtong upang bigyan diin ang pagiging natatangi ni Hesus bilang nagiisang Anak ng Diyos na may kalikasan ng Diyos, hindi katulad ng mga mananampalataya na mga inampon lamang bilang anak ng Diyos sa pamamagitan ng pananampalataya.