Is a person considered disobedient if they carry out one of God's commands without being convinced of it?

If one's lack of conviction regarding a religious matter means not comprehending its wisdom while still submitting and complying, then a person is not considered disobedient. There are religious commands whose wisdom is not apparent to many people, and this constitutes a trial and a test, known as a devotional rationale (illah ta'abbudiyyah).

Every ruling in Islamic law has a wisdom behind it. It may be that the devotional aspect of obeying Allah's commands, without a detailed understanding of their wisdom, is intended to increase faith and submission to Allah, and to accept what the mind is incapable of grasping. A servant needs to comprehend the secrets of legislation to increase certainty in the wisdom of the Sharia, and also to submit to what they cannot grasp, to test the sincerity of their faith.

However, if the lack of conviction is due to believing that the matter is devoid of wisdom or benefit, then this is a bad assumption about Allah Almighty, and necessitates repentance, as Allah says: ﴿And We did not create the heaven and the earth and what is between them aimlessly. That is the assumption of those who disbelieve, so woe to those who disbelieve from the Fire.﴾ [Saad:27], and He said: ﴿But no, by your Lord, they will not believe until they make you judge concerning that over which they dispute among themselves, and then find within themselves no discomfort from what you have judged and submit in full submission.﴾ [An-Nisa:65]. Therefore, it is obligatory upon the believer to receive Allah's rulings with acceptance, obedience, and submission.