手前

[thetazuo]

飲み干したグラスは、今度はなかなか満ちることがなかった。ただで頂戴している手前、文句を言う筋合いでもないが。

Context: the protagonist is drinking and talking with another man, who pours some beer into the protagonist’s glass for free.

By the way, does the bold 手前 refer to the speaker (俺) himself (I just have the beer for free)?

 

[Techref]

Hi
In this dialogue ,
手前　means “in this 'kind of' situation”
The next linking sentence would be something the speaker himself would need to do.
ただで頂戴している手前、文句を言う筋合いでもないが。
In this situation since I gotten it free of charge, there isn’t a reason for me to complain.

Please visit the links below for more examples =)
1. 手前

 

[SoLaTiDoberman]

~~ C している手前 = considering C, taking C into account.
This is a set phrase in Japanese.
"Considering it's free, "

 

[j-Adore]

One crucial point yet to be mentioned:

手前 has a negative connotation of owing someone something and feeling rather bad about it.


自分自身、何かに負い目を感じているような時に、「手前」は使われます。

e.g.: 一度ノーと断った手前、今さら頼みに行くのも気が引けるな...

 

[Flaminius]

Sense of indebtedness is, like j-Adore said in #4, is a nuance that accrues in 手前. Other naunces include:
1. deference: お銀様の手前、ムクの無躾なのを叱りました (中山介山『大菩薩峠』「伯耆の安綱の巻」)
2. face-saving: そんなに疑われると、子供の手前、恥かしくってねえ (梅崎春生「凡人凡語」)
3. sheer conformity: 少しは世間の手前も考えなさい (『大辞泉』 q.v. Sense 3)