Psalm 105 has no title and names no author; 1 Chronicles 16 places some of its verses in a song of thanks when the ark came to Jerusalem. The psalm opens with ten calls to action, among them give thanks, call on his name, sing, tell, glory, seek, and remember. Worship here means telling God's story aloud so that each new generation will know it.
The center of the psalm is the covenant. He has remembered his covenant forever, the word which he commanded to a thousand generations. God promised Abraham, Isaac, and Jacob the land of Canaan when they were but a few men in number. He protected the wandering families and warned kings: Don't touch my anointed ones! Do my prophets no harm! Even hard events served his plan. He called for a famine and sent Joseph ahead, who was sold for a slave until Yahweh's word proved him true.
The psalm then retells the exodus without mentioning Israel's failures, which Psalm 106 will confess. God sent Moses and Aaron, showed signs in the land of Ham, and brought his people out with joy. He gave a cloud for a covering, fire for light, quail, bread from the sky, and water from the rock. Verse 42 gives the reason for it all: For he remembered his holy word, and Abraham, his servant. The goal was that they might keep his statutes and observe his laws.