1 Samuel 12:23 is a passage that is still on my mind from a few days ago

Moreover, as for me, far be it from me that I should sin against the Lord by ceasing to pray for you…

How/why is it a sin against the Lord not to pray for someone? Here are a few thoughts to contemplate (Written in the first person)…

It is a sin against the Lord because… I’m relying on myself rather than God in the situation.

It is a sin against the Lord because… I don’t believe God is important enough to consult for the person/event.

It is a sin against the Lord because… I am ignoring the command TO pray.

It is a sin against the Lord because… I am arrogant in my heart toward God.

It is a sin against the Lord because… I don’t believe Scripture.