Contradiction with Matthew 15:24
This verse states Jesus was sent only to the lost sheep of Israel, contradicting the idea of widespread mercy and salvation mentioned in Zechariah 10:6 for the house of Judah.
Matthew 15:24: But he answered and said, I am not sent but unto the lost sheep of the house of Israel.
Contradiction with Romans 9:18
This verse suggests God's mercy is selective, which contradicts the promise in Zechariah 10:6 of showing mercy and saving the entirety of the house of Judah.
Romans 9:18: Therefore hath he mercy on whom he will [have mercy], and whom he will he hardeneth.
Contradiction with Hosea 1:6
This verse shows God's lack of mercy towards the house of Israel, contradicting Zechariah 10:6 which speaks of bringing them back in mercy.
Hosea 1:6: And she conceived again, and bare a daughter. And [God] said unto him, Call her name Loruhamah: for I will no more have mercy upon the house of Israel; but I will utterly take them away. [Loruhamah: that is, Not having obtained mercy] [no...: Heb. not add any more to] [but...: or, that I should altogether pardon them]
Contradiction with Isaiah 27:11
This verse indicates that God would not have mercy on Israel, which stands in contradiction to the promise of mercy in Zechariah 10:6.
Isaiah 27:11: When the boughs thereof are withered, they shall be broken off: the women come, [and] set them on fire: for it [is] a people of no understanding: therefore he that made them will not have mercy on them, and he that formed them will shew them no favour.
Contradiction with Romans 11:7
This verse implies that not all of Israel obtained salvation, which contrasts with the inclusive promise of salvation in Zechariah 10:6.
Romans 11:7: What then? Israel hath not obtained that which he seeketh for; but the election hath obtained it, and the rest were blinded [blinded: or, hardened]