Jesus repeatedly and consistently stated that everything in the OT was the infallible word of God. And he explicitly rejected the excuse by modern Christians that the NT is a replacement for the OT. Matthew 5:17 claims that Jesus says, "Do not think that I have come to abolish the Law or the Prophets; I have not come to abolish them, but to fulfill them. For I tell you truly, until heaven and earth pass away, not a single jot, not a stroke of a pen, will disappear from the Law until everything is accomplished." That "Law" was the OT and "every stroke of pen" in it.
To treat anything in the OT as other than God's word and Jesus' own will is to reject the NT as well. So, it is logically impossible to be Christian and not fully accept the OT, and also any admission of problems with the OT is inherently a criticism of Jesus himself.
Here are some more quotes from Jesus regarding the divine truth of the OT:
‘The Scripture cannot be broken’ (John 10:35). He referred to Scripture as ‘the commandment of God’ (Matthew 15:3) and as the ‘Word of God’ (Mark 7:13). Then in countless places he refers to the stories of the OT (Cain and Abel, Moses, Lot, etc.) as unassailable truth as they were written and makes no revisions to them.
If anything, the NT was written after Jesus died, so he never said anything to verify the divinity of what is in the NT. So it is dishonest and self-contradictory for any "Christian" to even treat the NT as more important than the OT, let alone dismiss anything in the OT as not part of Jesus' teachings.