'Messengers' in the Bible

When John's messengers had gone, Jesus began to speak to the crowds about John: "What did you go out into the wilderness to see? A reed shaken by the wind?

He sent messengers on ahead of him. As they went along, they entered a Samaritan village to make things ready in advance for him,

If there is any question about Titus, he is my partner and fellow worker among you; if there is any question about our brothers, they are messengers of the churches, a glory to Christ.

And similarly, was not Rahab the prostitute also justified by works when she welcomed the messengers and sent them out by another way?