Explain why value, honor, and religion, are three themes of Beowulf and how are they important in life today.
I wouldn't necessarily consider "value, honor, and religion" to be themes of Beowulf, instead, they are character traits that the main character (from the title) possesses. Beowulf, as a hero, is successful due to his values, which include a sense of honor and religious faith. Because he values other's lives above his own, he is willing to risk death to save others. Because he values a favor given to his father, he repays the favor after his father's death.
When he defeats the first two monsters, Grendel and Grendel's mother, he pays honor to both King Hrothgar (whose kingdom and people he saved) and his own King, Hygelac. He honors his men by sleeping in the same quarters as they do, treating them as equals. He honors King Hrothgar's wife by promising to take care of her sons should anything happen to her husband. Finally, because the original story was finally written down (it is said) by a Christian monk, it was told that Beowulf honors God, throughout the story, as the source of his strength and many other blessings as well as someone to be thanked.
Today, these characteristics serve as points of comparison for what our society would consider modern-day heroes. The question that the ancient story of Beowulf presents to its modern-day readers is, "Are the qualities that were once considered necessary for true heroism--value, honor, religious faith--still necessary and valued today?"