Haribol again Prabhu !!! I am no authority ,of course, But I think that you can always explain to whoever you are preaching that all this activities are supported in the shastras (you can add that the shastras are older than any other scripture and authorized by the parampara etc. just to prove their authenticity for doubting minds :})as ways to be connected with the Divine. Another explanation that you can offer is that devotional activities (i.e. performed to please God) makes you gradually become dettached from mundane material activities and makes you a spiritual person...
Also you can tell that even the mundane activities can become spiritual if they do it with the intention of pleasing God. And if they aren't still convinced, ask them for simply chant the Holy Name. The Mahamantra will help them awake bhakti inside their hearts...
Anyways this is just my humble opinion... Excuse my bad english...

Thanks for posting this good question, prabhu.

Particularly when I’m talking to westerners (usually Christians), I try to relate to them that Bhakti is devotional service, and there are basic devotional practices we follow. Instead of using the Sanskrit, I use the English, and I focus on the five most familiar to them: hearing, chanting, remembering, praying, temple/deity worship. I explain that these are ways of serving/worshipping God that nearly all the major religions follow. We are all doing these things. We do them because no matter what religion, there’s scripture in essentially all the religions in which God says ‘do these things in remembrance of me’. So, in Bhakti yoga we say the same thing.

I also use Srila Prabhupada’s great example of the difference between asking for our daily bread, and offering Krsna whatever He might like to eat, to emphasize the service
mood and how that’s a big difference between Bhakti and the others.

Also, to reinforce the process, I explain that our Acaryas have provided very explicit, step-by-step instructions for practicing this process, and for seeing the results. So we’re not left to wonder if God liked it, or if we did it right, and He actually received it. We have a science for God Consciousness that shows us how to ensure this process is working, end to end. (And hopefully by this point, the person is still listening!!)

You have so many nice answers. I'll see if I can add anything. You have the Srimad Bhagavatam (God's autobiography) wherein many descriptions of actions that are pleasing to the Lord. And most of all we have Lord Chaitanya, God, showing us what he likes.

all glories to sri guru & goranga!!

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