Deuteronomy 30:11-14 (New Revised Standard Version)
Surely, this commandment that I am commanding you today is not too hard for you, nor is it too far away. It is not in heaven, that you should say, "Who will go up to heaven for us, and get it for us so that we may hear it and observe it?" Neither is it beyond the sea, that you should say, "Who will cross to the other side of the sea for us, and get it for us so that we may hear it and observe it?" No, the word is very near to you; it is in your mouth and in your heart for you to observe.
Romans 10:5-13 (New Revised Standard Version)
Moses writes concerning the righteousness that comes from the law, that "the person who does these things will live by them." But the righteousness that comes from faith says, "Do not say in your heart, 'Who will ascend into heaven?' (that is, to bring Christ down) or 'Who will descend into the abyss?'" (that is, to bring Christ up from the dead). But what does it say? "The word is near you, on your lips and in your heart" (that is, the word of faith that we proclaim); because if you confess with your lips that Jesus is Lord and believe in your heart that God raised him from the dead, you will be saved. For one believes with the heart and so is justified, and one confesses with the mouth and so is saved. The scripture says, "No one who believes in him will be put to shame." For there is no distinction between Jew and Greek; the same Lord is Lord of all and is generous to all who call on him. For, "Everyone who calls on the name of the Lord shall be saved."