We have beheld (tetheāmetha). Perfect middle of theaomai as in 1Jo 4:12, though the aorist in 1Jo 1:1; Joh 1:14 (etheāsametha). John is qualified to bear witness (marturoumen as in 1Jo 1:2) as Jesus had charged the disciples to do (Act 1:8).
Hath sent (apestalken). As in 1Jo 4:9, though apesteilen in 1Jo 4:10.
To be the Saviour of the world (sōtēra tou kosmou). Predicate accusative of sōtēr (Saviour), like hilasmon in 1Jo 4:10. This very phrase occurs elsewhere only in Joh 4:42 as the confession of the Samaritans, but the idea is in Joh 3:17.