﴿ مِنْ أَجْلِ ذَٰلِكَ كَتَبْنَا عَلَىٰ بَنِىٓ إِسْرَٰٓءِيلَ أَنَّهُۥ مَن قَتَلَ نَفْسًۢا بِغَيْرِ نَفْسٍ أَوْ فَسَادٍۢ فِى ٱلْأَرْضِ فَكَأَنَّمَا قَتَلَ ٱلنَّاسَ جَمِيعًۭا وَمَنْ أَحْيَاهَا فَكَأَنَّمَآ أَحْيَا ٱلنَّاسَ جَمِيعًۭا ۚ وَلَقَدْ جَآءَتْهُمْ رُسُلُنَا بِٱلْبَيِّنَٰتِ ثُمَّ إِنَّ كَثِيرًۭا مِّنْهُم بَعْدَ ذَٰلِكَ فِى ٱلْأَرْضِ لَمُسْرِفُونَ ﴾

“Because of this did We ordain unto the children of Israel that if anyone slays a human being-unless it be [in punishment] for murder or for spreading corruption on earth-it shall be as though he had slain all mankind; whereas, if anyone saves a life, it shall be as though he had saved the lives of all mankind. And, indeed, there came unto them Our apostles with all evidence of the truth: yet, behold, notwithstanding all this, many of them go on committing all manner of excesses on earth.”

Please check ayah 5:34 for complete tafsir.