For those of us that consider a week to be from Monday to Sunday, let me welcome you all to a new week. I decided to say this because I know many start counting the week from Sundays.
Whatever the case may be, Monday signifies the beginning of a new week in virtually all Nigerian society. Mondays are considered "Ojo Aje" among the Yoruba-speaking people of Nigeria and all over the world. While the 'Ojo' in the nomenclature literarily means 'day', the 'Aje' part refers to a popular deity in Yorubaland - the goddess of wealth.
In other words, 'ojo aje' means the day dedicated to the goddess of wealth. This is why many Yorubas believe that Mondays are sacrosanct for finding wealth through various means, including daily jobs.
Aje, according to the belief, has the power to enrich and foster economic prosperity on individuals and a town. If Aje smiles on you, you are considered economically made for life. The deity herself is a daughter of another deity known as 'olokun'. Olokun refers to the owner of the sea. This is why the full name of the deity of wealth is 'Aje Olokun' and she is usually worshipped around water bodies.
Those who desire wealth but have been struggling sometimes consult spiritual houses where they are told to worship the Aje deity. The paraphernalia of worshipping aje include fruits of different kinds and cowries.
More on the Aje deity can be found in the following links: