Surah Anfal (8) Ayah 24

O you who believe! Give your response to Allah and His Messenger, when He calls to that which will give you life; and know that Allah comes in between a man and his heart, and that it is He to whom you shall (all) be gathered.

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This ayah is directly addressed to the believers and tells us respond to Allah and His Messenger (saw), meaning what we obey and follow the commands and not just believe. Calling to that which gives life can refer to the Quran and its Guidance. It has blessings and benefits in this world and the Hereafter when used to reform yourself. It implies that without this we are no different than those who are dead, who are unable to benefit themselves. The soul (ruh) needs a deen to sustain it. Those without a sound belief are like the dead.

When Allah comes between a man and his heart can mean that Allah helps the believer in deflecting what may cause him harm or take him away from the Guidance or life that is mentioned before. He keeps the heart alive. In a way it gives hope in Allah and that He knows what is in your heart and will help you.

And the last part mentions death. Allah will resurrect everyone who lived on this earth and they all will be questioned about their lives. This reminds of how short this life is and there is a purpose for it: to worship Allah.