«إن أحدكم يجمع خلقه في بطن أمه أربعين يوما نطفة ثم يكون علقة مثل ذلك ثم يكون مضغة مثل ذلك ثم يبعث الله إليه ملكا ويؤمر بأربع كلمات ويقال له: اكتب عمله ورزقه وأجله وشقي أو سعيد ثم ينفخ فيه الروح فإن الرجل منكم ليعمل بعمل أهل الجنة حتى لا يكون بينه وبينها إلا ذراع فيسبق عليه الكتاب فيعمل بعمل أهل النار فيدخل النار وإن الرجل ليعمل بعمل أهل النار حتى ما يكون بينه وبينها إلا ذراع فيسبق عليه الكتاب فيعمل بعمل أهل الجنة فيدخل الجنة»
The Prophet (peace and blessings be upon him) said:
"Indeed, the creation of each one of you is gathered in his mother's womb for forty days in the form of a drop of fluid (nutfah); then for the same number of days it remains a clot of blood ('alaqah); then for the same number of days it remains a lump of flesh (mudghah). Then Allah Almighty sends to it an angel who is commanded with four things, and it is said to him: 'Write down his deeds, his provision, his appointed time of death (lifespan), and whether he will be wretched or blessed.' Then the soul is breathed into it. So indeed, a man among you keeps doing the deeds of the people of Paradise until there remains between him and Paradise only the distance of an arm's length, then what has been written overtakes him, and he begins doing the deeds of the people of Hell and enters Hell. And indeed, a man keeps doing the deeds of the people of Hell until there remains between him and Hell only the distance of an arm's length, then what has been written overtakes him, and he begins doing the deeds of the people of Paradise and enters Paradise."
Hadith Referenceصحیح الجامع الصغیر / حرف الألف / 1543