Sins and their evil affects on you
And whatever of misfortune befalls you, it is because of what your hands have earned. And He pardons much.
[Qur'aan 42:30]
Ibn al-Qayyim writes:
فمن خاف الله آمنه من كل شيء، ومن لم يخف الله أخافه من كل شيء
He who fears Allaah [and abstains from sins], He keeps him safe [and feeling secure] from everything, and he who does not fear Allaah [and indulges in sins], He makes him fear everything.
If you want to enjoy the feeling of peace and security, the secret lies in obeying Allaah. Fear Him, and stay away from the things He has forbidden. If you do that, you will have peace. You will feel safe.
In contrast, if you indulge in those things He has ordered and warned you to stay away from, then fear will be instilled into your heart. You will fear, and then feel secure. You will fear over trivial things.
Ibn al-Qayyim writes
وسر المسألة: أن الطاعة توجب القرب من الرب سبحانه، فكلما اشتد القرب قوي الأنس، والمعصية توجب البعد من الرب، وكلما زاد البعد قويت الوحشة
And the secret of the matter is that obedience [to Allaah] brings a person closer to his Lord and every time closeness increases the feeling of happiness and friendliness increases. And disobedience takes away the slave from his Lord, and the further the slave gets from his Lord the stronger the feeling of melancholy and desolation becomes.
What Ibn al-Qayiim writes is something I have personally experienced in life.
On the days I try my best to avoid sins and do as many good deeds as possible to near Allaah, I feel the least fear. As a matter of fact I feel no fear. If I imagine the worst of situations and the worst of diseases happening to me it still does not cause me to fear in the least.
On the other hand, during the days when my good deeds decrease and my sins increase, even a shuffling in my garden as I leave for Fajr terrifies me.
Sins will take you away from Allaah. You will fear trivial things and peace will be no where to be found.
Obey Allaah, stay away from what He has warned you to stay away from, and do as many good deeds as you can with utmost sincerity and fear will never come your way.
Ibn al-Qayyim writes:
ومن عقوباتها: أنها تمحق بركة العمر، وبركة الرزق، وبركة العلم، وبركة العمل، وبركة الطاعة
وبالجملة أنها تمحق بركة الدين والدنيا، فلا تجد أقل بركة في عمره ودينه ودنياه ممن عصى الله، وما محقت البركة من الأرض إلا بمعاصي الخلق، قال الله تعالى: {ولو أن أهل القرى آمنوا واتقوا لفتحنا عليهم بركات من السماء والأرض} [الأعراف: 96]
وقال تعالى: {وأن لو استقاموا على الطريقة لأسقيناهم ماء غدقا - لنفتنهم فيه} [الجن: 16 - 17]
And from the evil effects of disobedience is that it destroys blessing in regards to life, provision, knowledge, doing good deeds, and obedience.
In summary it destroys the blessings of Religion and this worldly life. The one who disobeys Allaah will not find even least amount of blessing in regards to his age, Religion, or life.
Blessing on earth does not decrease except by the sins of the creation.
Allaah says in the Qur'aan:
And if the people of the towns had believed and had the Taqwa (piety), certainly, We should have opened for them blessings from the heaven and the earth, but they belied (the Messengers). So We took them (with punishment) for what they used to earn (polytheism and crimes, etc.).
[Qur'aan 7:96]
And Allaah says:
And [ Allah revealed] that if they had remained straight on the way, We would have given them abundant provision
[Qur'aan 72:16]