The Two of Similar Nature 
Its Definition: They are the two letters that have the same articulation point, but differ in characteristics. They can be in one word as in: 
or within two words, as in:
.
The difference in characteristics can be between one to four. is divided further into three divisions, just as 
was divided:
1. 
2. 
3. 
The Two Small Similar in Nature
This occurs when the first of the two letters is saakin, and the second voweled. There are special cases of merging ( 
) in , if the letters are not specifically mentioned in this next section, then the rule is 
.
The Merging of the small two similar in nature 
The merging ( ) is this case is not absolute as is in the case of , instead it occurs in special letters. This means that not every time there are two letters of the same articulation point but different characteristics, the first one saakin, and the second voweled, there is an . The following letters merge into the letters below them:
We will now go through these letters that have the same articulation point, but differ in characteristics and give examples of the merging that occurs when their relationship is “small”, meaning the first letter of the two similar in nature is saakin and the next of the two is voweled. Part of the above table will be covered in this tidbit, and the remaining, insha’ Allah in the next tidbit.
These first examples are all examples of complete merging, meaning the first letter of is merged into the second letter and no trace of the first letter’s characteristics remain in the recitation.
1. 
into 
. This occurs in two places in the Qur’an:
2. into . This occurs several times in the Qur’an, some examples are:
Click here to listen to aayah 4 of Al-Kaafiroon
3. into 
. This also occurs repeatedly in the Qur’an, an example is:
