Based on the 2nd commandment and other biblical texts and stories, historic Reformed and Presbyterian churches have taught and practiced the Regulative Principle of Worship: we are to worship God in no other way than he has commanded in his word (HC Q/A 96, WLC Q/A 109). There are several different applications and implications of the RPW. Here are a few based on Exodus 32 and some other verses.
1) True worship is not a democratic endeavor. What is right and proper in Christian worship is not based on what a majority of people think is right and proper. Many Israelites approved of the golden calf but it was still blatantly disobedient and offensive to Yahweh.
2) True worship does not cater to the consumer. What people want or are looking for should not determine how Christians’ worship God. True Christian worship isn’t based on what attracts people – such as entertainment, celebrity, comfort, and what is the most fun or relevant. Israel no doubt enjoyed the rowdy party around the golden calf, but Yahweh still detested the calf and Israel’s worship.
3) True worship is not grounded on emotions and feelings. Just because a person feels like a certain style of worship is good doesn’t make it so. Feelings, emotions, and experiences can be false or sinful and should not drive our worship principles. The Israelites felt the need to have the golden calf since Moses was taking so long, but it was still a breach of God’s command and thus a terrible sin that was punished severely.
4) True worship is not a matter of preference. The standard for true worship is not what I like, what you prefer, what the youth want, or what unbelievers will be attracted to. Aaron’s preference was to throw a wild party for Yahweh around the calf, but Moses still told Aaron that he had sinned against Yahweh.
5) True worship is (obviously!) a matter of truth. Christians must worship the triune God in Spirit and truth – God’s word is truth (Jn. 4:23 & 17:17). In other words, worship must be clearly biblical: in worship we must sing the truth, pray the truth, preach the truth, and listen to the truth. If something is not commanded in Scripture, it cannot be part of corporate worship. Reformed churches are reformed – and always reforming – according to the word of truth. This also has to do with one of the solas: Sola Scriptura. The word is our ultimate authority. In worship, we should want to do what God wants us to do: “thy will be done” even applies to worship.
6) True worship forbids formality. A person can worship the true God using true words, but the heart might still be far from the Lord (Is. 29:13). Just going through the motions of corporate worship is not true worship. So we must repent of formality, hate it, fight it with a renewed appreciation for the gospel of sovereign grace, pray that our hearts would be “in” worship, and prepare our hearts for corporate worship.
There are more implications and applications of the RPW (I encourage you to think of some). These are some evident ones based on the following resources I’ve read over the years: Give Praise to God, A Better Way, With Reverence and Awe, Dining with the Devil, and The Necessity of Reforming the Church, among others.