Moderation in Eating, Drinking and Expense

• Eat and drink, not in excess but in moderation and do not waste [7:31]
  

• Do not spend unnecessarily, nor devour, eat away or waste away Allah's bounties. Allah does not approve of the extravagant or the wasteful [6:141]
  

• [Surely those will attain a good recompense] who , when they spend, are neither extravagant nor niggardly, but hold a medium way between these two extremes [25:67]
  

• Do not be extravagant in dissipating or squandering wealth or property in a way that is not right or on objects that are vain [17:26]
  

• Verily, the extravagant are the brethren of SHAYATEEN and SHAYTAN is very ungrateful and unappreciative of his Lord [spending not his resources where they ought to be spent and squandering them on the wrong objects] [17:27]

{Israaf is spending more than one ought to spend. Tabzeer is to spend on objects where one ought not to spend

Israaf is from the root s-r-f which leads to the following meanings:

-To be ignorant, unmindful, heedless, negligent, unacquainted, or mistaken in heart or mind
-To eat away, waste away, or devour
-To exceed or transgress the just or right bound or limit or measure
-To act extravagantly, exorbitantly, immoderately
-To go waste because of overflowing [e.g. of water in a container]

Israaf is opposite of Qassdun, which (i.e. Qassadun) has the following meanings:

-To follow the right, middle and most just way in an affair and do not exceed the due bounds therein
-To act in a moderate manner, in a manner that is between prodigality and parsimoniousness, in an affair
-To act in a manner that is contrary to extravagance
-To keep within the due bounds and content with a middle course

Tabzeer is from the root b-z-r, which leads to the following meanings:

-To scatter, disperse, dissipate
-To be extravagant in expenditure
-To dissipate, squander [wealth or property] by extravagant expenditure and destroy, consume, waste or ruin in a way that is nor right or that does not behove

Source: quranicteachings.co.uk