The sacrifice of the wicked is detestable-- how much more so when brought with evil intent!
He said to them, “If any of you has a sheep and it falls into a pit on the Sabbath, will you not take hold of it and lift it out? 12 How much more valuable is a person than a sheep! Therefore it is lawful to do good on the Sabbath.”
If you then, though you are evil, know how to give good gifts to your children, how much more will your Father in heaven give the Holy Spirit to those who ask him!"
13 The blood of goats and bulls and the ashes of a heifer sprinkled on those who are ceremonially unclean sanctify them so that they are outwardly clean. 14 How much more, then, will the blood of Christ, who through the eternal Spirit offered himself unblemished to God, cleanse our consciences from acts that lead to death, so that we may serve the living God!
How much more severely do you think someone deserves to be punished who has trampled the Son of God underfoot, who has treated as an unholy thing the blood of the covenant that sanctified them, and who has insulted the Spirit of grace?
Since we have now been justified by his blood, how much more shall we be saved from God's wrath through him!
2 Corinthians 3:9
If the ministry that brought condemnation was glorious, how much more glorious is the ministry that brings righteousness!
Arguing by how-much-more seems to be one of the favorite methods used by the writers of the Bible. Is this a logically valid way of proving or is it just idiomatic? In any case, what is its significance since it is used so frequently in the Bible?
It seems to be related to https://en.wikipedia.org/wiki/Argumentum_a_fortiori as pointed out by Chaz' comment.