Matthew 13: 15-17 (NIV)
15For this people's heart has become calloused; they hardly hear with their ears, and they have closed their eyes. Otherwise they might see with their eyes, hear with their ears, understand with their hearts and turn, and I would heal them.'
16But blessed are your eyes because they see, and your ears because they hear.
17For I tell you the truth, many prophets and righteous men longed to see what you see but did not see it, and to hear what you hear but did not hear it.
Romans 10:9-10 (NIV)
9That if you confess with your mouth, "Jesus is Lord," and believe in your heart that God raised him from the dead, you will be saved.
10For it is with your heart that you believe and are justified, and it is with your mouth that you confess and are saved.