Jamieson, Fausset and Brown on Luke 21:4

4. of their abundance--their superfluity; what they had to spare," or beyond what they needed.

of her penury--or "want" (Mr 12:44)--her deficiency, of what was less than her own wants required, "all the living she had." Mark (Mr 12:44) still more emphatically, "all that she had--her whole subsistence." Note: (1) As temple offerings are needed still for the service of Christ at home and abroad, so "looking down" now, as then "up," Me "sees" who "cast in," and how much. (2) Christ's standard of commendable offering is not our superfluity, but our deficiency--not what will never be missed, but what costs us some real sacrifice, and just in proportion to the relative amount of that sacrifice. (See 2Co 8:1-3.)