Jn 1:28 ... 'These-things' happened in Bethany beyond the Jordan where was the-one John baptizing.

A "testimony" is code for 45 dialog words in verses 20-27 that form a polygon. Two phrases of 19 narrator words in verses 19 and 28 form two bookends for the testimony ... "Kai autē estin hē marturia tou Iōannou" (And this is the Testimony of the John). "Tauta en Bēthania egeneto peran tou Iordanou, opou ēn ho Iōannēs baptizōn" (These-things in Bethany happened beyond the Jordan where was the-one John baptizing).

The word "tauta" (these things) are John's testimony, the 45 dialog words he said in verses 20-27: ... "Egō ouk eimi ho christos. Ouk eimi. Ou. Egō fōnē boōntos en tē erēmō. Euthunate tēn hodon kuriou. Ego baptizo ev udati, mesos humon hesteken hon humeis ouk oidate, ho opisō mou erchomenos, ou ouk eimi egō aksios hina lusō autou ton imanta tou hupodēmatos" (I am not the Christ. Not I-am. No. I, a-voice crying in the wilderness. Make-straight the way of-the Lord. I baptize in water; among-you has-stood one whom you not do-know, the-one coming after me, of-whom not am I worthy that I-should-untie of-him the thong of-the sandal). John's 45 word testimony forms a rectangle held in his hands from above and below.