Who is Mindful of Buddha?

One of the methods to ‘combine’ Pure Land and Zen practice
is that the one who practise mindfulness of Amituofo’s (Amitabha Buddha) name
also asks oneself ‘Who is the one mindful of Amituofo?’

Who is the one who practises mindfulness of Buddha?
One who is truly mindful would realise
that the one mindful of Buddha is one’s Buddha-nature.

One who is truly mindful would realise
that the one mindful of Buddha is no one else in particular.
But you need to be perfectly mindful to know this perfectly – to be a Buddha!