Bible study from December 16, 2019, looking at Psalm 50
Psalm 50 pictures God calling all his people to stand before Him. As He speaks to them (and to us) in judgment, He testifies against us that we have not always worshipped Him as we should. In Old Testament terms, His people have not been offering animal sacrifices as they should. They were going through the motions, but their hearts were not really where they should be. It is as if they thought they were doing something good for God and deserved His favor; and yet their everyday life forgot God and His will and cast His Words away. (See especially v. 16-22, for a very strong statement of their sins.)
God reminds the people that He does not need their sacrifices. He already owns all animals and all things. (See v. 8-13.) The people needed, rather, the forgiveness and mercy He offered them through these sacrifices (which were really a preparation of the one great sacrifice that His only Son, Jesus, would make on the cross, as “the Lamb of God Who takes away the sins of the world.” (John 1:29) See also passages like Hosea 14:1-4). People needed to worship, then, in a humble and grateful way, repentant for their sins, with thanksgiving for what God was doing for them and trusting His help for them and then glorifying Him. (See especially v. 14-15 and v. 23, in Psalm 50). In thanks and gratefulness to God, then, people will also try to “order their ways rightly” according to His will.
Jesus warns us, too, in New Testament days, of hypocrisy in our own worship, seeking personal glory and favor from God and others (see Matthew 6:1-18, for example) or just saying the words in worship, with our own hearts not really in what we do (see Matthew 15: 7-9). Rather, we are to come humbly and thankfully to God, knowing our own sins and needing His mercy, too. That is what the confession and absolution in our Sunday worship is to remind us of and actually give to us - the forgiveness of God. (See also New Testament passages like Hebrews 13:15, Philippians 4:4-7, and Romans 12:1-8, as examples of the right attitude, of gratitude and thanks to God for His mercy and love.)