Al-Ahzab 33:23

Mina almu/mineena rijalun sadaqooma AAahadoo Allaha AAalayhi faminhum man qadanahbahu waminhum man yantathiru wamabaddaloo tabdeela

Among the believers are men true to what they promised Allāh. Among them is he who has fulfilled his vow [to the death], and among them is he who awaits [his chance]. And they did not alter [the terms of their commitment] by any alteration -

Among the believers, there are men who came true to the covenant they had with Allah. So, some of them have fulfilled their vows (by sacrificing their lives in the way of Allah), and some of them are (still) waiting, and they did not change (their commitment) in the least.