What does Judges 13:20 mean?
At the suggestion of a stranger—whom they apparently believe to be a prophet (Judges 13:2–11) or "man of God"—Manoah and his wife are offering a burnt offering to God. This is in the form of a young goat and grain. It is their sincere expression of thanks and devotion; praise to the Lord for the wonder He has worked in the promise of a baby (Judges 13:12–19).Now something astonishing happens. The stranger—whom they apparently believed to be merely human—suddenly rises into heaven in the flame of their burnt offering. The prior verse carefully noted the pair were watching, so this is no misunderstanding or optical illusion. They are staggered by seeing this supernatural event. It brings sudden realization about the Person to whom they've been speaking. This is "the angel of the LORD," seemingly God Himself in human form.
The awestruck couple do the only appropriate thing: they fall in the prostrate position of worship, humility, and submission before God. However, the same realization has left Manoah afraid for their lives (Judges 13:21–22).