Some translations set each line of poetry farther to the right than the rest of the text to make it easier to read. The ULB does this with the poetry in 12:18-21, which are words from the Old Testament.
This chapter has much to say about how God's people are to obey the Sabbath. Jesus said that the rules that the Pharisees made up did not help people obey the Sabbath the way God wanted them to. (See: [[rc://en/tw/dict/bible/kt/sabbath]])
No one knows for sure what actions people perform or what words they say when they commit this sin. However, they probably insult the Holy Spirit and his work. Part of the Holy Spirit's work is to make people understand that they are sinners and that they need to have God forgive them. Therefore, anyone who does not try to stop sinning is probably committingblasphemy against the Spirit. (See: [[rc://en/tw/dict/bible/kt/blasphemy]] and [[rc://en/tw/dict/bible/kt/holyspirit]])