Assalaamu alaykum. I heard that there is a hadith that says that modesty is half of faith, and another one says that ghusl (ritual bath) is half of faith; how do we understand these, and how do we relate them to the hadith about marriage being half of faith?

All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad is His slave and Messenger.

After intensive search, we have not come across a Hadeeth with the wording: “Modesty is half of faith.” Rather, what is well-known is a different wording: Saalim ibn 'Abdullah (ibn 'Umar) narrated from his father that the Prophet passed by a man from the Ansaar who was preaching to his brother because of his modesty; thereupon, the Prophet said to him, “Leave him, for modesty is part of faith.” [Al-Bukhari and Muslim]

Also, Abu Hurayrah narrated that the Prophet said, “Faith consists of more than seventy branches, … and modesty is a branch of faith.” [Al-Bukhari and Muslim]

Likewise, we have not come across a Hadeeth that states that ghusl is half of faith. The famous Hadeeth is the one narrated by Abu Maalik al-Ash’ari in which the Prophet said, “At-Tuhoor (purification) is half of faith.” [Muslim]

What is meant by purification here is cleansing with water after one of the following: passing urine, feces or wind, or having had sexual intercourse, etc.). An-Nawawi, explained what is meant by “Purification is half of faith,” when interpreting Saheeh Muslim, as he said:

“There is a difference of opinion about the Prophet’s saying: 'Purification is half of faith.' It was said that its meaning is that the reward for it is multiplied until it amounts to half of the reward of faith, and it was said that faith and ablution both cancel the sins preceding them because ablution is valid only with faith, so ablution being dependent on faith is in the meaning of half of it; and it was said that faith here means the prayer, as Allah says (what means): {And never would Allah have caused you to lose your faith.} [Quran 2:143]; purification is a condition for the validity of prayer, so it is considered as half, and it is also not necessary that half means exactly its literal meaning as half, and this view is the closest to the correct meaning.”

As regards the third Hadeeth, “Marriage is half of faith (the religion)”, then this Hadeeth was reported with a different wording than the one you mentioned, but it has the same meaning. Anas narrated that the Prophet said, “Whomever Allah has blessed with a righteous wife, He has indeed helped him in half of his religion, so let him fear Allah in the other half.” [At-Tabaraani, Al-Haakim and Al-Bayhaqi - Al-Haakim graded its chain of narration as Saheeh (sound)]

In the narration by Al-Bayhaqi, the Prophet said, “If a man is married, he has indeed completed half of his religion, so let him fear Allah in the other half.” [Al-Albaani graded it Saheeh (sound) in Saheeh at-Targheeb wat-Tarheeb]

Al-Munaawi interpreted the meaning of how marriage equals half of the religion, as he said in Faydh al-Qadeer, “A person who marries has completed half of faith”, and in another narration: ‘half of his religion, so let him fear Allah in the remaining half;’ he [the Prophet] considered piety as two halves: a half due to marriage and a half for all other things. Abu Haatim said, 'What upholds the religion of a person is mostly his private parts and his stomach, and by marrying, he preserves one of them.'”

Based on the above, saying that something is half of faith or half of the religion is based on different considerations, each understood on its context, and it does not necessarily have to be a real half.

Allah knows best.