"Then an angel from heaven appeared to Him and strengthened Him." (Luke 22: 43, NIV)
In the Garden of Gethsemane, an angel descended to comfort Jesus in anticipation of his followers' denial. In Guardians of the Galaxy, Vol. 2, Quill finds himself standing alone in the imploding core of his father. His teammates reluctantly fled, except for Yondu, his surrogate father. At a key moment, Yondu instructs Peter to use his heart to turn the tables on Ego’s final big play. Like Jesus, our hero must singularly reject doubt in the face of his father, God, but can't make the decision on his own. He needs a little encouragement from the mortal world.
Star-Lord passes on immortality and godship so that he can save the universe. In the New Testament, Jesus allows himself to be killed so he can be resurrected as an example for future generations who would follow his words and teachings. This is where the movie finesses the themes from a religious text into a statement on evangelism.
Besides Peter Quill’s arc in the film, every other character (with maybe the exception of Baby Groot, whose only sin is innocence) has to take responsibility for his or her past, even if the actions that weren't all that thought out. Jesus’s arc in the Bible says something similar: ask forgiveness from God and love thy neighbor. Guardians divorces the devotion from the message. Star-Lord's journey advocates for personal choice and responsibility beyond what’s expected of you by your family and community. The New Testament is much less forgiving when it comes to denying your father and taking personal responsibility.
After his death, Christ rose from the grave and told his disciples to spread his Gospel on the new Christian way of life. They followed, which is how we wound up with scripture, The Bible, and church. Peter rejects Ego's plans to "spread" his message i.e. blueberry jelly blobs that consume entire planets. That may feel like a drastically different plot outcome, but both Christ figures sacrifice for all life after identifying the human experience. Jesus decided to spread his father’s light throughout the universe, bathing us all in it’s comfortable and limiting glow. Peter Quill decides that the best way to do that is to be the best individual you can be, which is why, unlike Jesus, he'll be back for an inevitable sequel.