´It was narrate from Jubair bin Nufair that 'Aishah said:` "The Messenger of Allah used to be keen to fast on Mondays and Thursday."
Related hadith on this topic
Explanation & Benefits
Shaykh Dr. Abdur Rahman Freywai
English Commentary:
1:
One reason given for this is that on these two days, deeds are presented before Allah, as narrated from Abu Hurairah (radi Allahu anhu) that the Messenger of Allah (sallallahu alayhi wa sallam) said: “Deeds are presented (to Allah) on Mondays and Thursdays, so I love that my deeds be presented while I am fasting.” Another reason is that which is mentioned in the narration of Muslim, that when the Messenger of Allah (sallallahu alayhi wa sallam) was asked about fasting on Monday, he said: “That is the day on which I was born and on it I was sent as a Prophet, or on it revelation was sent down to me.”
Source: Sunan al-Tirmidhi – Majlis ‘Ilmi Dar al-Da‘wah, New Delhi Edition, Page: 745
Maulana Ataullah Sajid
Benefit:
The meaning of "showing concern" is that they would fast with intention and would strive not to miss fasting on that day. The reason for this concern is clarified in the next hadith.
Source: Commentary on Sunan Ibn Mājah by Mawlānā ‘Atā’ullāh Sājid, Page: 1739