Contradiction with Ecclesiastes 5:2
Advises not to be rash with words, while Matthew 7:28 notes Jesus astonished crowds with authoritative teaching.
Ecclesiastes 5:2: Be not rash with thy mouth, and let not thine heart be hasty to utter [any] thing before God: for God [is] in heaven, and thou upon earth: therefore let thy words be few. [thing: or, word]
Contradiction with Proverbs 21:23
Suggests guarding one's mouth to avoid trouble, contrasting with Jesus speaking openly and astonishing in Matthew 7:28.
Proverbs 21:23: Whoso keepeth his mouth and his tongue keepeth his soul from troubles.
Contradiction with James 1:19
Encourages being slow to speak, whereas Matthew 7:28 shows Jesus teaching openly and extensively.
James 1:19: Wherefore, my beloved brethren, let every man be swift to hear, slow to speak, slow to wrath: