For if I preach the gospel, I have no reason for boasting, because I am compelled to do this. Woe to me if I do not preach the gospel! (1 Corinthians 9:16)
Everyone who is saved by the grace of God is called to testify and share the gift of salvation. That, however, is not the same as the call to preach, but is merely an illustration of our deeds and showing love to one another which can be used in preaching.