What do we learn from "Im Atah Hachinosa Libecha"?
Rashi: If you would intend [to understand] afflictions.
Mesilas Yesharim Perek 17: Early Chasidim would delay an hour before praying, to prepare their hearts to Hashem and cast off all stray thoughts.
Devar Eliyahu: These two verses are the four parts of Teshuvah. Hachinosa Libecha is the first - regret in the heart.
Malbim: In spite of [man's limitations], you can perceive that man's deeds are not forced. If your heart desired to do something, immediately "u'Farasta Elav Kapecha" - your hands do it. Your heart rules over your hands. Nothing forces you. Also your heart, "Hachinosa Libecha" - you decide what you want!
What is the significance of spreading your hands to Hashem?
Rashi: This is supplication.
Devar Eliyahu: This is Viduy.
