In the world of advertising, there has to be as much initial coverage as possible, even to the point of saturation. Advertising campaigns are planned and executed like a military assault. Some companies mount the assault first, and then gauge the response. Only if the response is good do they finally make the product! In other words, the advertising is literally about nothing!
The way of the Gospel is the opposite of this. Everything begins on a small scale: Jesus spoke of seeds hidden in the ground. Seeds are very small, but they are not nothing; they are a tremendous something; to understand even a single seed in its very essence would be to understand the universe.
Every living thing (including ourselves) has a small beginning. That is the mark of reality. But big talk is usually a substitute for reality and a sign of nothing. Loud is often shallow. There is a kind of Christian advertising (let's not call it preaching) that has none of the depth of the Gospel. This is already visible in the gospels, and Jesus himself had to discourage it. He frequently enjoined silence on people, and even on demons (Mt 16:20; Mk 8:30; Lk 4:41, etc.). This is called 'the Messianic Secret'.
Why, we might ask, did Jesus want to make a secret of himself? We usually imagine him rather wanting to make himself known! The reason is that people expected the Messiah to be a political leader, and that is exactly what he did not want to be. He was not a politician, and not an advertiser. These speak in generalities to the generality of people. But he spoke from the heart to every kind of person. And he has spoken to countless millions of people throughout the centuries. He has been heard because his voice is humble, gentle and particular.
We need to listen carefully to ourselves (talking and thinking), to hear whether our voice is the voice of the one who was "meek and humble of heart". How are we to talk, for example, to teenagers or even younger people? Certainly, they will be stone-deaf to any political-sounding diatribe; and no advertising gimmickry will make any impact on them, because the advertisers do it so much better. Our voice is too general, too theoretical, too impersonal, too political, too distanced from their experience - and even from our own experience. It is too often not a caring voice at all but a tactical one, showing little genuine sympathy for the actual human being before us, in his or her struggle.
As in all the ages of the past, what convinces people is the full presence of a person, not lectures, experience rather than theory, small things rather than big talk.