Is Zakat due on financial inheritance from one's father for one year only, or in installments over 8 years, or entirely in one payment, knowing that the amount is available and needed for living expenses?

A Muslim must learn the rulings of Islamic law and seek to fulfill the rights of Allah. If zakat becomes due, it is a debt owed and cannot be discharged except by paying it. It is not permissible to delay it when one is able, for the Prophet, peace be upon him, said: "Allah's debt is more worthy of being paid."

The share of each person's wealth must be calculated. If it reaches the nisab (minimum threshold), then the zakat for all past years that the wealth has circulated must be paid. The obligation is not discharged except by doing so.

However, if one is unable to pay the zakat due to not possessing enough funds or needing the money for life's necessities, there is no sin in the delay. They must, however, hasten to pay it as soon as they are able.

As for the profits generated from depositing money in an interest-bearing (usurious) bank, they are a debt owed and must be disposed of by spending them on the welfare of Muslims or by giving them to the poor and needy. A poor person is permitted to give this charity to themselves and their dependents.