In Matthew 5:21-26, Jesus makes it clear that you can also kill with words by oppressing and restricting others. Anyone who openly declares that they are angry with their brother or casts the Jewish ban raka (dupe) or fool (madman, godless) on him destroys life.
Likewise, unforgiveness destroys life. Or when guilt is ignored and the other person only comes into his own through judgement.
Anyone who calls someone ungodly, excludes them from the community of believers and robs them of the opportunity to repent is, according to Jesus, counted among the ungodly.
So killing can also be done by agitation, character assassination, silence, evasion, by denying the other person their rights or by refusing to be reconciled.
James even says (4:17): “So whoever knows the right thing to do and fails to do it, for him it is sin.”
The opposite of killing is not just letting the other person live but promoting them.
Jesus shows us that we have all killed in one way or another. We all need forgiveness and change through the Holy Spirit.