Musar do Samuela I 18:24

What caused Shaul to begin to ambush David? Only honor as written: "And the women sang to one another as they celebrated: 'Saul has struck down his thousands, and David his tens of thousands'... And Saul eyed David from that day on" (Shmuel 18:7-9).

The beginning of the פרשה speaks about the gift of the land of Israel which is a patently "good" gift both in its manifest and in its hidden aspects. The land is situated "opposite" a corresponding ארץ ישראל in the Celestial Regions. Both the terrestrial land of Israel and the Celestial land of Israel has areas of varying degrees of sanctity. We have learned (Keilim 1,6) about the ten respective layers of sanctity of terrestrial ארץ ישראל culminating in the Holy of Holies. Moses thought that the lands of the kings Sichon and Og, i.e. the East Bank of the Jordan, already contained some level of the sanctity common to the whole of ארץ ישראל. We will explain why he thought so later on. A leader who leads the people to take possession of the Holy Land acquires great spiritual advantages. The authority of Jewish leaders is not of the same caliber as that of the Gentile kings or rulers. While the Gentiles derive their authority from physical power and material attributes, this is not so in the case of leaders of the Jewish people. Their authority is rather of the caliber of Heavenly authority. To be more specific: Leaders are appointed according to superior intellectual qualities, according to the ability of the individual in question to lead the people in Torah observance. As soon as the first Jewish king, Saul, was anointed king by the prophet Samuel he was granted Holy Spirit, as we know from Samuel I 10,11-12: הגם שאול בנביאים, "Saul too has joined the ranks of the prophets." One of the reasons the kingdom was transferred to David was that there was no one as qualified as David as far as Torah scholarship was concerned. G–d was with him to such an extent that any religious rulings pronounced by David were always accepted by his colleagues as binding. In addition, no one excelled like David in singing the praises of the Lord. These are the considerations that made Moses so desirous of remaining the leader who would bring the Jewish people into the Holy Land. He knew that if he were to be granted this request he would further perfect his personality, would be granted even greater insights by G–d. He wanted to fulfill those commandments which can only be fulfilled on the soil of the land of Israel, and he was certain that by doing so he would ascend still higher spiritually (Sotah 14a).

Another way of explaining our Psalm may be that David felt the need to apologize for taking credit for his humility, i.e. he apologized שלא גבה לבו, for having his humility become common knowledge. This in itself would rate as a form of boastfulness. He apologized, for not having remained silent, i.e. אם לא שויתי ודממתי נפשי. Whichever may be the case, the subject of this Psalm is the extreme importance of practicing humility.