Those who are playing in idle avocation.
who are in their blundering, heedless.
those who are in plunging, playing
Who amuse themselves by vain talk
Those who, they are in a plunge/an engagement in conversation playing/amusing
vain discourse and took serious matters lightly
Those who are playing in pursuits
Who sportingly indulge in idle talk
Those who are playing a game of negligence, rapt in falsehood (i.e., absurdity)
Who indulge in idle talk and who are busy in vain pursuits
Who are playing in falsehood