mint, anise, and cummin… weightier matters of the law — refers to the gospel according to Matthew, chapter 23, where Jesus says:
Woe unto you, scribes and Pharisees, hypocrites! for ye pay tithe of mint and anise and cummin, and have omitted the weightier matters of the law, judgment, mercy, and faith: these ought ye to have done, and not to leave the other undone. Ye blind guides, which strain at a gnat, and swallow a camel.