'Testimony' in the Bible

Jesus ordered him to tell no one [that he might happen to meet], “But go and show yourself to the priest, and make an offering for your purification, just as Moses commanded, as a testimony (witness) to them [that this is a work of Messiah].”

And as for all those who do not welcome you, when you leave that city, shake the dust off your feet [breaking all ties with them] as a testimony against them [that they rejected My message].”

for I have five brothers—in order that he may solemnly warn them and witness to them, so that they too will not come to this place of torment.’

This will be a time and an opportunity for you to testify [about Me].