Is the percentage agreed upon with a security guard for him to leave his job for me—with my prior intention to donate a tenth of my wealth if Allah grants me a job—considered charity or a bribe? And what is the ruling on this action?

If you are qualified for the job, then there is no harm in interceding on your behalf, as it is a good intercession. However, if you are not qualified, then it is not permissible to intercede for you, and that is a bad intercession and deception.

Scholars have differed on the permissibility of taking a fee for intercession (the price of influence). Some have deemed it permissible, while others have prohibited it, or considered it disliked, or offered a detailed explanation. The most preponderant view regarding the price of influence is that it involves a detailed explanation: If the intercession is something obligatory for the intercessor, then it is not permissible to take a fee. If it is not obligatory for him, such as interceding for private sector jobs, then if he expended effort and work in it, taking a fee is permissible. If he did not expend effort, then there is a difference of opinion on it.

According to the view that permits it, it is permissible to give this man a fixed sum or a percentage of the salary for a specific period. However, it is not permissible to give him a tenth of the salary indefinitely, due to the uncertainty, gharar (definition) (excessive risk/ambiguity), and injustice involved.

Also, one should not obligate oneself to a specific amount by way of a vow. Rather, it is recommended to give charity from what is easily available after providing sufficiently for oneself and one's dependents, in accordance with the hadith (definition): "The best charity is that which is given when one has sufficiency, and begin with those whom you support."