In fact, there is no hard and fast line that could be drawn between tahajjud and isha. Once the isha time begins, it is better to say it not later than 12 o’clock, that is the midnight. Because we know from the tradition that sometimes when A.S. was late, so sahaba, particularly Hazrat Bilal is known to have knocked at his door and told him that it is getting very late and it is almost midnight. So then A.S. came out and didn’t say, no it is not late, you can say it up till morning. So when sahaba were waiting and they thought it was getting late, A.S. agreed to it is getting late.
Only that much is mentioned in the tradition. Beyond that, there is no definite halfway line between isha prayer time and tahajjud prayer time. Though for the end of tahajjud prayer we know, when the morning begins, the tahajjud time ends. So in reality what happens is this, that after the maghrib prayer, the time of isha begins and we are expected to sleep before tahajjud and get up, because that is also inferred from the holy Quran. So the no man’s land between isha and tahajjud should be that period of sleep and rest.
According to the holy Quran, that should also be some hours. Because A.S. is definitely told that previously you have been staying almost awake the entire night and you had very little to sleep, but now we ask thee to increase your sleep to at least one third of the night. Or half of the night or a little more. So that shows that for the long nights, you could extend, you can minimize your sleep to one third. Because in the winter nights, the nights are longer, and one third is quite enough, it amounts to a few hours. In the summer night, you could reduce it to half or even more, with the result that tahajjud time and sleep time become almost equal, equally balanced. So it all depends upon the changing days or the duration of days.
So from that I infer that there should be a few hours time between tahajjud and isha prayer, because sleep time is the separating factor. So if you work from an hour and a half to tahajjud, and a few hours of sleep, it would almost come back to the middle of the night. So that judgment, which is based on intuition, seems to be a correct judgment. As far as Hazrat Musleh Maud is concerned, I remember during my childhood, that he was of the opinion that normally, under ordinary circumstances, mid of the night should be treated as the end of the time for isha.
But if you are on a journey or under different, I mean, under compelling conditions, and you are not going to sleep anyway, then even if you miss that mark, isha will be still within time, technically speaking.
