Brief Answer:
Yes, sins are ranked according to their effects. According to Qurʾān and ḥadīth, there are several situations in which minor sins are considered as major sins. When this occurs, the minor sins will have the same consequences and punishments as major sins. An otherwise minor sin is considered as a major sin if an individual does the following:
persistently commits minor sins
considers one’s sins as trivial
openly expresses happiness while committing a sin
commit a sin out of blatant disobedience and rebellion
becomes arrogant in the face of Allah’s reprieve
openly commits sins
commits a sin while holding an important position or position of influence

Detailed Answer
An otherwise minor sin is considered as a major sin if an individual does the following:

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Persistently commits minor sins
Repeating minor sins causes them to become major sins. This also occurs if a person commits just one sin, but does not ask for forgiveness or think about repenting. This will be considered persistence in committing sin. The Holy Qurʾān has said the following about those who are righteous: …and (those) who knowingly do not persist in what [sins] they have committed.

Imām ʿAlī (ʿa) has said, “Avoid repeating sins, because it is among the greatest of misdeeds.”
Consider one’s sin as trivial
Underestimating one’s sin will cause it to become a major sin. Imām ʿAlī (ʿa) has said, “The greatest of sins is that act of disobedience which the sinner considers trivial and negligible.”
Openly express happiness while committing sin
To enjoy and openly express happiness while committing a sin causes that sin to become greater and increases its punishment. Imām ʿAlī (ʿa) has said, “The worst of the worst is a person who becomes happy while doing that which is bad.”

Imām as-Sajjād (ʿa) has also said, “Avoid becoming happy while committing sin, as this expression of joy is worse than the sin that is being committed.”
Commit a sin out of blatant disobedience and rebellion
The Holy Qurʾān says, “As for he who has been rebellious and preferred the life of this world, his refuge will indeed be hell.”
To become arrogant in the face of Allah’s reprieve.
A minor sin becomes greater when a sinner considers Allah’s reprieve, or the fact that His punishment is not immediate, as a sign of His pleasure or contentment with that sin. Allah has said in the Holy Qurʾān, “And they say to themselves, ‘Why does not Allah punish us for what we say?!’ Let hell suffice them: they shall enter it, and it is an evil destination!”

The fact that hellfire is promised to those who become arrogant when they are not immediately punished proves that they committed a major sin.
Openly commit sins
Openly committing sin causes a minor sin to become a major sin. This is perhaps due to the fact that sinning openly indicates that a person has no problem in disobeying Allah. An action that leads to the corruption of society and brings a certain normalcy to sinning is considered as a major sin. Imām ʿAlī (ʿa) has said, “Avoid committing sin openly, as this is one of the most terrible of sins.”

Imām ar-Riḍā (ʿa) has also said, “The reward of a person who hides his good acts is equivalent to 70 good acts, while the fate of a person who openly commits sin is wretchedness.”
Commits a sin while holding an important position or position of influence
The sin of a person who holds a position in society is not equal to that of others. The minor sins of these individuals will be considered as major sins. This is because their sins occur in two dimensions: an individual dimension and a societal dimension.

The sins of people in leadership and positions of influence can lead to the misguidance of society and weakening of people’s faith. It is because of these devastating effects that Allah’s accounting of those in positions of leadership is different from that of the common people. In the Qurʾān, Allah addresses the people of knowledge who create innovation in religion: “Had he (Muḥammad) faked any sayings in Our name, We would have surely seized him by the right hand and then cut off his aorta, and none of you could have held Us off from him.”

Allah has addressed innovators of religion and those who perpetuate distortions in religion in several places in the Qurʾān, but He has never used such strong language in those places. However, because of the Noble Prophet’s purity, high level of knowledge, awareness, and influence, his sin would be considered major. Imām Jaʿfar aṣ-Ṣādiq (ʿa) has said, “70 sins of the ignorant will be forgiven, before one sin of the scholar is forgiven.”

The Noble Prophet (ṣ) has also said, “If the scholars of religion and heads of government become corrupt, then the people will also become corrupt.”