Matthew 6:4
ESV - 4 So that your giving may be in secret. And your Father who sees in secret will reward you.
For follow-up discussion and general commentary on the topic. Comments are sorted chronologically.
When you give in secret, God will reward your good deed openly.
God see's all. He is ALL anyone should ever be concerned about. Secret or not...I would rather impress Him then people...when I give, etc.