Well thank you for a very important question. The answer is “Yes” and “No.” Confused? well, keep reading.
In The Ten Commandments one of them is “You shall not murder.” (Exodus 20:13) That is very plain, but people do kill others, but sometimes they do not mean to. Meaning it was an accident, an animal caused the death or maybe in a fight (this is 3,500 years ago). In the Old Testament, God, who is merciful, made five ‘Cities of Refuge’ where a person who had accidently killed someone could get to quickly before relatives came and took angry revenge. In the Cities of Refuge the person was safe and later on, would have a proper trial.
In the Ten Commandments ‘murder’ meant that you deliberately planned to kill someone and did it. That is called ‘wilful murder’. In some countries like the USA and China you can be put to death for that.
In the Old Testament (3,500 years ago) God killed thousands of his own people because He would not tolerate deliberate and wilful disobedience of His laws and instructions again and again. Some people treated God with distain, lied about things, and mocked his laws. There are many references to it in the Bible. On one occasion God had Joshua assemble all the family of Achan. He admitted his guilt and he and all his family and the animals he had, were stoned to death and stones heaped over them and ‘God's anger was abated’. That’s in Joshua Chapter 7. (That punishment made the rest more inclined to obey strict instructions I would think.)
Stoning to death by the town’s people was in God’s law…but God is merciful. On one occasion (see John Chapter 8 verses 3 to 11) the religious politicians tried to trap Jesus into giving a wrong answer about a woman caught in the act of adultery (the bloke must have run away). Jesus refused to answer. But under pressure Jesus said: “Alright, stone her to death but only he who has never sinned may cast the first stone.” That put them on the spot. Slowly they all left, having remembered their own sins, and Jesus said to the woman: “Where are they all, are there none left to accuse you?” She replied: “None, Sir.” And Jesus said to her: “Neither do I accuse you; off you go and leave your life of sin.” Compassion – that’s Jesus. Even today people still use the expression: “Are you going to ‘cast the first stone’?” meaning that person could be hiding his/her own guilt over some matter in the past but wanting to punish someone else.