"I am filled with pity" vs "I am pitiful"

If I am filled with pity for an individual / group (eg - the Syrian situation), I would probably say, "I am filled with pity for the individuals concerned," as opposed to "I am pitiful for the individuals concerned." Surely, logically, both should have the same connotations, but, "I am pitiful ..." turns myself into the subject, does it not? - rendering the latter sentence nonsensical.

Etymologically, surely these had the same meaning originally - am I incorrect in jumping to such conclusions?

Solution 1:

Both the words piteous and pitiful held both meanings of A) having pity for others and B) exciting pity from others. The OED records the historical usage as follows:

piteous A 1350-1750  
piteous B 1290-1887 

pitiful A 1491-1875
pitiful B 1450-1871

One might think that the direction of feeling took a reversal at some juncture, but the two senses overlapped for centuries. Today both words join pitiable as synonyms, but the how and why, as is usual, are difficult to trace.

Solution 2:

You are correct on both counts: "I am pitiful" implies that the subject is you; and yes, originally, pitiful meant "merciful, compassionate" (circa 1300 A. D.). See: http://www.etymonline.com/index.php?term=pitiful