05-Are Gospel Invitations to All?

Is it possible – is it right – for a preacher 1 to invite all sinners to
come to Christ, and to do so without preparing them for the
gospel, for Christ? Or does the preacher have to prepare sinners
by preaching the law to them before he invites them to come to
the Saviour? Do sinners have to undergo certain experiences
before they can feel they are invited to trust Christ, or have any
warrant to do so?