My mother-in-law entered the Catholic Church this past Easter because the mere actions and lifestyle of her daughter (and apparently me... the mind boggles) gave her the idea that maybe we had something she wanted too. It took 15 years, but she has directly confirmed that if we'd spent that time hammering her with Scripture and doctrine it wouldn't have worked.
There is a time for instruction, there is also a time for a living witness, confusing the timing can lead to disaster. Not everyone is equally suited for the task of instruction, a quick look around the religion forum proves that. I know I'm not, except in very few circumstances.
Everyone wants to be the mouth, nobody wants to be a toe.
Then, by all means, be silent