Back in parshat Noach, the Torah said that after Gd remembered Noah in the ark. The Torah there uses the word “Yizcor”. In Vayeara, Gd remembers Sara and gives her a child. In Vayera with Sara the word is Pakad. Same idea, but different word. Rashi comments in our parsha that Sara is remembered because she prayed for Avimelech to be healed. In Noah, Rashi remarks that Gd turned his strict judgment to mercy when he comments on “Vayizcor Elokim.” Rashi comments that the judgment was turned to mercy because the inhabitants did not corrupt their ways.
What is the qualitative difference between the two usages of remember. The Shikker Dovid would like to suggest that by Sara, she is actively acting righteously. She is actively seeking to assist others throughout her prayers. In Noach, they are refraining. This is a passive service to gd.
The lesson for the Shikker Dovid is that refraining from corrupt behavior is important. But true growth, real spiritual development comes from actions like Sara- proactive behavior.