He further states that God endowed him with strength like iron, which signifies that his courage in warfare was not ordinary but supernatural, a gift exclusive to the Almighty.
Although David possessed physical strength, he was not notably tall, as his sacred narrative illustrates; this likeness embodies something transcending human might. In the following verse, he declares that he was safeguarded and delivered solely by the grace of God. By referring to protection and salvation, he emphasizes that without God's miraculous preservation, he would have succumbed to numerous deadly assaults. Thus, God’s defense stands in stark contrast to all the weaponry and military provisions of warfare. Indeed, his speed, physical strength, and combat expertise would have been ineffectual against the formidable King Saul and his entire army, had it not been for the saving protection granted by God, which empowered and upheld him.
The subsequent statement, "And thy discipline shall correct me in the end, and thy chastisement shall teach me this," refers to the same grace of God that provided guidance and growth amid trials and perplexing circumstances, preventing him from straying or erring. Here, the term punishment pertains to the instruction derived from the law; yet, such instruction is attainable only through the grace of God.