Great thoughts and a pure heart, that is what we should ask from God.

God is looking for clean hands and a pure heart.

Pure heart begets pure thoughts.

Each one sees what he carries in his heart

A wounded heart can with difficulty be cured. [Ger., Doch ein gekranktes Herz erholt sich schwer.]

Only the heart without a stain knows perfect ease. [Ger., Ganz unbefleckt geniesst sich nur das Herz.]