David faces the harsh scolding of his older brother, Eliab, and attempts to defuse the tension by drawing a clear line between simply talking and actually taking action. David questions why his brother is attacking him at this specific moment. He points out that even if Eliab has a habit of getting angry at him for things he has done in the past, in this current situation, he has not actually done anything at all [מצודת דוד, ביאור שטיינזלץ].
When explaining his intentions, the primary approach among commentators is that David tries to downplay the situation. He insists that he is merely speaking words. Since he has not taken any physical action, and supposedly has no intention of doing anything further, there is no reason for his brother to be upset.
On the other hand, another perspective suggests David's response carries a much deeper meaning. Instead of minimizing the situation, David is subtly hinting that while he has not acted yet, he fully intends to take action later. The insults directed at the armies of God are a severe issue that demands a real response. By keeping his answer intentionally vague, David manages to quiet the immediate argument and prevent his brother from speaking to him any more harshly, while still holding onto his plan to act [חומת אנך].