Someone has said that a good interpretation of Psalm 33:2 might be: “praise ‘looks good’ on the upright.” The righteous are commanded to praise God, and it is fitting and comely when they do. But we may also infer a couple of other things from that statement:

First, NOT praising is NOT appropriate for God’s people. Those whose sins have been covered by the blood of Jesus on the cross, who have a home in heaven, and a personal relationship with God, have every reason to rejoice. It is inappropriate when God’s people do not praise Him — either because they are absent from public worship, or refrain from worship when they ARE present, or when they continually walk with downcast countenances. It does not reflect well on our Master when His servants do not rejoice!

But secondly, because it says “praise is becoming to the upright”, we can also infer that praise is NOT becoming for those who are NOT upright! It doesn’t “fit.”
Sometimes people have a tendency to try to “make up” for their lack of righteousness, by the fervor of their worship; in other words: “I know I am not living right, so I will make up for it by really praising God in church.” It is good, generally speaking, to emphatically worship God in church — but fervent worship does not atone for our lack of obedience. “To obey is better than sacrifice”, Samuel reproved Saul. Instead, cleanse your hands, and purify your hearts, as James commands, and then your sacrifice of worship will be acceptable to God – but not before.

This is a call for each of us to examine our own lives: does praise look good on you?