This verse Al-Baqarah 2:56 ⧉ refers to death, which suggests that the thunderbolt had killed them. Since the Israelites had always been mistrusting Sayyidna Musa (علیہ السلام) ، he feared that they would suspect him of having taken the men to a solitary place and got them slaughtered. So, he prayed to Allah to save him from such a vile accusation. Allah granted his prayer, and gave those a new life.