It is impossible to answer the question asked,"On what ground can one get divorce?", without knowing what is the Lord’s position with regards to divorce. As previously stated in an event of separation, according to the scriptures neither party is permitted to remarry and must remain sexually pure.
God is not the author of confusion nor does the scriptures contradict itself.
In his response to the Pharisees question in Mathew 19 vs 3 - 9 & Mark 10 vs 2-12. as to why then did Moses gave the instruction to give a bill of divorcement and put the wife away, Jesus answered,
“For the hardness of your heart he (Moses) wrote you this precept”
Often times this part of the scripture is ignored when the subject of divorce is discuss.
The question pose to us here is, What is this hardness of heart that Jesus is talking about?
While pondering on this question, we must be reminded that, our conscience is that inner sense of right and wrong that God has put in every human heart (Rom. 2:15) and therefore it is informed by God’s Word of truth. Even if our conscience is misinformed, it is always a sin to violate it (Rom. 14:14, 23; James 4:17).https://youtu.be/4HJgCJE2ma8