A person cries because of a reason. At times one cries because of mercy and kindness; at times because of fear; sometimes because of fondness and-love; sometimes due to intense happiness; sometimes due to pain or-sorrow; at times due to the oppression of someone. Among these there is the crying of tawbah (repentance) which is an outcome of some sin committed.
The best and most valuable type of tears are those that are shed in remorse over sins and tawbah.
People cry because of loss of something important to them. For example (May Allah save us), a wife dying, or a son dying.
Shedding tears is due to the connection with the thing that is lost.
أَفَمَن شَرَحَ اللَّهُ صَدْرَهُ لِلْإِسْلَامِ فَهُوَ عَلَىٰ نُورٍ مِّن رَّبِّهِ ۚ فَوَيْلٌ لِّلْقَاسِيَةِ قُلُوبُهُم مِّن ذِكْرِ اللَّهِ ۚ أُولَٰئِكَ فِي ضَلَالٍ مُّبِينٍ
So is one whose breast Allah has expanded to [accept] Islam and he is upon a light from his Lord [like one whose heart rejects it]? Then woe to those whose hearts are hardened against the remembrance of Allah . Those are in manifest error.
[39:22]
Sins have two effects:
1-they make your heart hard, and,
2- they make you lose the connection with Allah
If we are invited to the court of a king, we will not scratch our beard or heads e.t.c. we will present ourselves with utmost propriety. If we realise the greatness of Allah then we will not be scratching our beards etc, and even if we move a hand to do so, we will quickly move the hand back in place.
When Hadhrat Abu Huraira RA fell ill and was passing away, he had become thin and pale, his eyes had sunken in. Despite of his poorly state, he was not upset, whereas he had a tranquillity in his heart, because he was going to meet the prophet peace be upon him soon.
No-one is saying don't eat and drink or get married. Do everything within the boundaries of shariah.
'Abdullah bin Shikh-kheer Radiyallahu 'Anhu says: ''I attended the noble assembly of Rasulullah Sallallahu 'Alayhi Wasallam. He was performing salaah. Because of his crying, such sound emmitted from his chest, like that of a boiling pot''.
When performing salah behind an imam, there is no need for you to pray takbeer loudly. When you stand in front of a King in this world, you won't even speak. In your salah you should have such concentration that you don't pray loudly.
يَا أَيُّهَا النَّاسُ اتَّقُوا رَبَّكُمْ ۚ إِنَّ زَلْزَلَةَ السَّاعَةِ شَيْءٌ عَظِيمٌ
يَوْمَ تَرَوْنَهَا تَذْهَلُ كُلُّ مُرْضِعَةٍ عَمَّا أَرْضَعَتْ وَتَضَعُ كُلُّ ذَاتِ حَمْلٍ حَمْلَهَا وَتَرَى النَّاسَ سُكَارَىٰ وَمَا هُم بِسُكَارَىٰ وَلَٰكِنَّ عَذَابَ اللَّهِ شَدِيدٌ
O mankind, fear your Lord. Indeed, the convulsion of the [final] Hour is a terrible thing.
On the Day you see it every nursing mother will be distracted from that [child] she was nursing, and every pregnant woman will abort her pregnancy, and you will see the people [appearing] intoxicated while they are not intoxicated; but the punishment of Allah is severe. [22:1,2]
May Allah give us the tawfiq