Earlier quoted context omitted.
I just realized that [7] probably works only because of [8] - I always give my Twilio phone number to people and pretend with my family that this is my main number.
That is why he mentioned "verified phone number" I guess. When you have verified your own phone number you can send texts from it as well.
https://support.twilio.com/hc/en-us/articles/223135427-What-...