Psalm 118 is a song of great confidence in the Lord. The Lord brings victory to his people, and they praise him! Our perfect victory is in Jesus, who triumphed over death when he died for us. We have the same joy and confidence as the psalmist, in the God we serve.
Psalm 119 is a long psalm about the importance of keeping God’s law. The psalmist knows he need to keep focused on God. Living for God doesn’t mean living however we want, but we need to learn to live God’s way – he has laws and precepts for our lives, and we need to know them and live by them. That means (Psalm 119: 21) not wandering away.