Solomon's failure is a profound tragedy magnified by the stark contrast between his extraordinary spiritual standing and his inability to heed an explicit warning. His immense wisdom, his greatness, and the rare privilege of receiving direct prophecy from God should have been more than enough to prevent such a downfall [ביאור שטיינזלץ].
The command to avoid other gods carried a strict obligation for Solomon to keep idol worship completely out of his own home. The primary danger was that his sons would watch their mothers worship idols and eventually adopt those same practices. God issued this warning to keep Solomon on the proper path, which was the key to securing the future of the monarchy, preventing the exile of the Israelites, and saving the Temple from destruction [רלב״ג].
Yet, Solomon violated this directive. The gravity of his sin is exceptionally severe specifically because the warning came directly from God Himself. Disobeying such a direct, personal command is an offense without a remedy. This mirrors the tragic fate of the prophet from Bethel, who directly defied God's word and was consequently killed by a lion [מלבי״ם]. The intimate nature of Solomon's relationship with God is underscored by the history of their communication. Although God spoke to Solomon three times over the course of his life, only two of these instances are counted as actual appearances, as one event consisted solely of speech rather than a full prophetic vision [מלבי״ם].