Bringing mind/ body into a sattvic (calm, bright, balanced state)
Understabding that it is when the nature of mind is either in rajas (forceful) or tamas (dull) that there are vrittis (thought waves) that are not useful for our development/evolvement, (working into the boat pose with this).
This can cause doubt and anxiety because we do not have a sattvic mind (- calm, cheerful).
Only when body mind and intelligence are purified (-sattvic- calm, open, bright) we can surrender and not expect anything in return; this is the mastery over the mind and anything presented to mind then can just shine back to the object. Ref Patanjali 1,36 140, 1,41