The life of Abinadi was preserved so that he could finish his message. Nephi was also protected by the power of God when his brothers were harboring murderous thoughts. He said, In the name of the Almighty God, I command you that ye touch me not, for I am filled with the power of God, even unto the consuming of my flesh (1 Nephi 17:48). The pattern continues with Samuel the Lamanite. Although he was up on the city wall, the stones and arrows could not hit him (Hel 16:2). Because of the power of God that was protecting Samuel, the wicked Nephites would have been no more accurate had they shot at point-blank range. So we see that the Lord will preserve his prophets until they have delivered their message to the very last word.
Elder Cree-L Kofford
"…having been confounded by the word of God’s servant and following the command of their king, the wicked priests of Noah attempt to lay their hands on him that they might slay him. At this critical moment in the life of this great man, when his life hangs in the balance, his words reach out to us over a span of more than two thousand years. You can almost see his shoulders square noticeably as he draws himself to his full height and majestically proclaims: ’Touch me not, for God shall smite you if ye lay your hands upon me, for I have not delivered the message which the Lord sent me to deliver’ (Mosiah 13:3; emphasis added).
“Can you feel the electricity of that moment? Can you begin to understand now why Abinadi is such a special prophet? Words like heroic, courageous, obedient, fearless, powerful, dynamic, and faithful all come flooding into your mind as you replay that moment in Abinadi’s life over and over in your mind; and as you do, Abinadi rises to the very heights of what a servant of God should be.” (Heroes From the Book of Mormon, p. 71)