The Old Testament, Deuteronomy 6:

4 “Hear, O Israel! The LORD is our God, the LORD is one! 5 You shall love the LORD your God with all your heart and with all your soul and with all your might. 6 These words, which I am commanding you today, shall be on your heart. 7 You shall teach them diligently to your sons and shall talk of them when you sit in your house and when you walk by the way and when you lie down and when you rise up. 8 You shall bind them as a sign on your hand and they shall be as frontals on your forehead. 9 You shall write them on the doorposts of your house and on your gates.

The New Testament, Mark 12:

28 One of the scribes came and heard them arguing, and recognizing that He had answered them well, asked Him, “What commandment is the foremost of all?” 29 Jesus answered, “The foremost is, ‘HEAR, O ISRAEL! THE LORD OUR GOD IS ONE LORD; 30 AND YOU SHALL LOVE THE LORD YOUR GOD WITH ALL YOUR HEART, AND WITH ALL YOUR SOUL, AND WITH ALL YOUR MIND, AND WITH ALL YOUR STRENGTH.

The Final Testament – Quran:

[39:3] Absolutely, the religion shall be devoted to GOD alone. Those who set up idols beside Him say, “We idolize them only to bring us closer to GOD; for they are in a better position!” GOD will judge them regarding their disputes. GOD does not guide such liars, disbelievers.

[2:62 and 5:69] Surely, those who believe, those who are Jewish, the Christians, and the converts; anyone who (1) believes in GOD, and (2) believes in the Last Day, and (3) leads a righteous life, will receive their recompense from their Lord; they have nothing to fear, nor will they grieve.