There is an important faith concept in Psalm 21 that is easily missed, the idea of giving thanks in advance. Human nature often moves us to live in anticipation of something and then we give thanks when it is received. The logic is pure and simple; why give thanks for something not received? On the other, do we not give thanks to God in advance because our trust is weak?
For the king trusts in the Lord; through the unfailing love of the Most High he will not be shaken. (v 7)
This psalm is paired with Psalm 20 as the prayer intercedes on behalf of the king so that as the leader is successful, the king’s people will be blessed as well. It is not a historical record, rather, the expressions of trust and belief and gratitude precede the battle or other travail and they demonstrate a faith rooted in the belief that the outcome will be positive. In other words, the prayer does not follow a demonstration of God’s faithfulness, it anticipates it. As we approach the day of Christmas we would do well to search our own hearts to see if we have developed this same attitude.