O Lord, my strength, and my fortress, my refuge in the day of affliction, the Gentiles shall come to You from the ends of the earth and say, “Surely our fathers have inherited lies, worthlessness, and unprofitable things.” Jeremiah 16:19.

Strength, ‘oz; Strong’s # 5797. Strength, power, security. This noun comes from the verb ‘azaz, “to be firm and strong.” Jeremiah waxes poetic in this verse in which he describes his God with poetic quality in Hebrew.
‘Uzi u-Ma’uzi (my strength and my fortress). ‘Oz is used in many OT verses Ps. 8:2; 46:1; 63:2, Isa. 12:2. A well-known verse is David danced joyfully before the Lord with all his strength (2 Sam. 6:14). Psalm 105:4 gives sagely advice and counsels us to “seek the Lord and His strength.”