The transmission of the teaching is like a widening cascade of light. The brightness is indivisible.
The transmission from one real person to another is called ‘I shin den shin‘. ‘Shin’ means heart/ mind, so it can translate as ‘from my heart to your heart’
We might assume there are two hearts, but my heart is this heart; your heart is this heart. This heart is the heart of this-ness–Indivisible.
Because this is so, transmission is intimate, non-dual, feeling. Each thing is the heart of all things. Each time is this time.