Suppose you were going to rob a bank and you heard the Adhaan so you stop to pray (it's Fardh) and then rob the bank - the prayer may well be worthless and "hypocritical" but you have obeyed Allah in fulfilling this Fardh act? Comment please?
It is evident from your question that prayer is fardh, so there is no need for further elaboration of the same.
- If a Muslim performs his prayers, the prayers forbids him from sins and wrong-doings. Allah (JJ), says in the holy Quran,
Recite [O Muhammad] what has been revealed to you of the Book and establish prayer. Indeed, prayer prohibits immorality and wrongdoing, and the remembrance of Allah is Greater. And Allah knows that which you do. [Quran 29:45]
Now I am coming towards your question:-
Prayer according to Quran:-
Maintain with care the [obligatory] prayers and [in particular] the middle prayer and stand before Allah , devoutly obedient. -- al-Baqara 2:238
And establish prayer at the two ends of the day and at the approach of the night. Indeed, good deeds do away with misdeeds. That is a reminder for those who remember. -- Hud 11:114
The Hadith of the Prophet PBUH:
Adullah ibn Mas‘ood may Allah be pleased with him said, "I asked the Prophet PBUH 'What is the best deed?' He (Prophet PBUH) said: 'Performing prayer in its due time.' I further asked, 'Then what?' He replied: 'Dutifulness toward parents.' I further asked, 'Then what?' He replied: 'Performing jihad in the Cause of Allah The Exalted.'" [Al-Bukhari and Muslim]
Fardh is an Islamic term which denotes a religious duty commanded by Allah (God) and its denial renders one to come out of the folds of Islam. Now, if somebody omits to perform any Fard without any valid shari'i reason, then such a person becomes a major sinner. So, there is no excuse for omission and missing of fard, whatsoever, anybody can't omit the salah (Fard). If somebody have faith in Allah, then prayers and righteous deeds will not let him to do the sin and evil.
إِنَّ الصَّلاةَ تَنْهَى عَنِ الْفَحْشَاءِ وَالْمُنْكَرِ