He is afraid that he may lose his job and he has some money; does he have to do Hajj with it?

In order for Hajj to be obligatory for the adult, it is stipulated that he should be financially and physically able for it, because Allaah says (interpretation of the meaning):

“And Hajj (pilgrimage to Makkah) to the House (Ka‘bah) is a duty that mankind owes to Allaah, those who can afford the expenses (for one’s conveyance, provision and residence)”

[Aal ‘Imraan 3:97]. 

The fuqaha’ interpreted financial ability as meaning that one has enough to cover food and transportation, i.e., the expenses of travel to and from the Sacred House of Allaah, if this cost is surplus to one’s basic needs and other expenditure as prescribed in sharee’ah, and to pay off his debts. 

What is meant here by expenditure is that he should have enough to cover his own and his family’s maintenance until he returns, and after he returns he should have enough to suffice him and those on whom he spends, such as the rent on property or salary or trade and so on. Hence he does not have to go for Hajj using the capital of his business, if he spends on himself and his family from its profits, and if taking away from the capital will result in a reduction in profits, such that they will not be enough for him and his family. For more information on this, please see the answer to question no. 11534. 

If you have the money that will be sufficient for you to do Hajj, and it is surplus to your needs, then you must go for Hajj, unless your fear of losing your job is a real fear based on strong circumstantial evidence, in which case you do not have to do Hajj. But if this fear is just an illusion and notion with no basis, then you have to do Hajj. 

As for the money that you have set aside for marriage, you do not have to do Hajj with it if you fear hardship for yourself in the event of delaying your marriage, rather you should give precedence to marriage. If there is any other money, you can use that for Hajj, otherwise Hajj is not obligatory for you because you cannot afford it. 

Ibn Qudaamah (may Allaah have mercy on him) said: If he needs to get married and he fears that it will be too difficult for him otherwise, then he should give priority to that, because it is obligatory for him and he cannot do without it, so it becomes part of his essential spending. But he has no such fears, then he should give priority to Hajj, because marriage is voluntary and should not take precedence over Hajj which is obligatory.

End quote from al-Mughni (3/88). 

See also the answer to question no. 27120. 

And Allaah knows best.