3 John 12 Demetrius has received good testimony from everyone and from the truth itself. We also add our testimony, and you know that our testimony is true.
John provides two other examples of those who followed the truth. He could be following his Jewish roots of having at least two witnesses to confirm the truth of a matter (Deuteronomy 17:6; 19:15). The key word in this verse is testimony (martyreō) repeated three times. Its basic meaning is to bear witness, affirm, or testify about a matter based on one’s convictions or experience. The verb used for Demetrius is in the perfect tense and with a passive voice. As used here, it indicates how others had watched or heard him over time and saw that he believed in and lived by the truth of the gospel. He had proven himself before others who could confirm their observations about him. To make this even more impressive is the word everyone, likely referring to believers, but unbelievers would also take notice. Demetrius did not live two lifestyles but was consistent in all he did. When his life was compared to the truth, there was no contradiction but full agreement. The contrast between him and Diotrephes could not be starker. One represented the bad and the other the good of verse 11. Gaius had a clear example to follow. It is assumed he would know Demetrius, who may have even been part of his fellowship.
John adds a second testimony of himself and others. The others included in this verse are not stated but could be those with some authority or those with John as he wrote this letter. The pronoun we is emphatic, adding to the significance of Demetrius’ testimony. Many people were watching and observing how he lived. The implied message is that one’s testimony to the truth can have a big impact on others. In this short letter, John gave Gaius powerful motivation by clearly identifying whom to imitate and whom not to imitate. How one lives out the truth in word and deed can influence others and help them come to faith in the one who is the Truth.