Question: I do not have time to practise Nianfo, but will chant in my mind (i.e. not aloud) when cycling, walking or going to sleep. Is this okay?
Answer: It is okay. However, if you really wish to benefit yourself and others more deeply with sincere Nianfo, it is important to take time aside to do only Nianfo; not only while doing something else, which mostly makes it half instead of wholehearted.
For example, when cycling, the mind will toggle between the road conditions and Amituofo’s name continually, instead of abiding on the name only, to develop stronger concentration. Chanting while going to sleep means your mindfulness will taper off and switch off, which is not optimal too.
You should still do your current Nianfo practices as much as possible, while doing something else, and when about to sleep, but you should ALSO do Nianfo only by itself, when wide awake, so as to express utmost sincerity as mindfully as you can – to connect more deeply to Amituofo.
There is no need to chant Amituofo’s name very loudly; just loud enough for yourself to hear will do. Most importantly, always with his name clearly in your mind, even if not aloud. Chant clearly and listen to it clearly to know you are doing Nianfo sincerely.
Here are the steps for a full Nianfo session: http://purelanders.com/2016/02/17/how-do-i-start-nianfo-practice They are taught in the ‘Understanding Amituofo Via Amitabha Sutra’ course. The next run is coming: thedailyenlightenment.com/courses Do come to learn more systematically and comprehensively.