I think, i.e. my interpretation, which should be well-known by now
that the practice His Holiness speaks of can be a practice that one formulates for oneself from non-conflicting sources. If one does find and form this practice, and it works, then stick with it. This is not easy to do, as I have discovered. One should carefully study a particular religion before plunging headlong into it, as many of us do, only to find out later that it doesn't suit us.
HHDL made a more detailed comment about it at
Dalai Lama Asks West Not to Turn Buddhism Into a "Fashion" | ZENIT - The World Seen From Rome "People from different traditions should keep their own, rather than change. However, some Tibetan may prefer Islam, so he can follow it. Some Spanish prefer Buddhism; so follow it. But think about it carefully. Dont do it for fashion. Some people start Christian, follow Islam, then Buddhism, then nothing.
In the United States I have seen people who embrace Buddhism and change their clothes! Like the New Age. They take something Hindu, something Buddhist, something, something
That is not healthy.
For individual practitioners, having one truth, one religion, is very important. Several truths, several religions, is contradictory.
I am Buddhist. Therefore, Buddhism is the only truth for me, the only religion. To my Christian friend, Christianity is the only truth, the only religion. To my Muslim friend, [Islam] is the only truth, the only religion. In the meantime, I respect and admire my Christian friend and my Muslim friend. If by unifying you mean mixing, that is impossible, useless."
Gandhi expressed something I take as similar to HHDL's comments (in part):
"...My own veneration for other faiths is the same as that for my own faith; therefore no thought of conversion is possible."