Albert Barnes Commentary Psalms 105:4

"Seek ye Jehovah and his strength; Seek his face evermore." — Psalms 105:4 (ASV)

Seek the Lord and his strength—Seek strength from him; seek that his strength may be imparted to you; seek him as a Being of almighty power, as One by whom you may be strengthened. The Septuagint and Vulgate render this, “Seek the Lord, and ‘be strengthened.’” Strength comes from God, and it is only by his strength that we can be strong. Only by our making use of his omnipotence in our own behalf can we discharge the duties and bear the trials of this life. Compare the notes at Isaiah 40:29-31.

Seek his face evermore—His favor. His smiling upon us, his lifting up the light of his countenance, is synonymous with his favor. See Psalm 24:6; Psalms 27:8. Compare the notes at Psalm 4:6.