Srimad Bhagavatam Canto 11, Chapter 21, Text 11

SB 11.21.11

saktyasaktyatha va buddhya
 samrddhya ca yad atmane
agham kurvanti hi yatha
 desavasthanusaratah
 
Translation: 
 
Impure things may or may not impose sinful reactions upon a person, depending on that person’s strength or weakness, intelligence, wealth, location and physical condition.
 
Purport: 
 
The Lord has described the purity and impurity of different places, times and material objects. According to the laws of nature, that which is impure contaminates a particular person in accordance with that person’s situation, as described here. For example, on certain occasions, such as a solar eclipse or just after childbirth, one must restrict the intake of food according to ritualistic injunctions. One who is physically weak, however, may eat without being considered impious. Ordinary persons consider the ten days following childbirth to be most auspicious, whereas one who is learned knows that this period is actually impure. Ignorance of the law does not save one from being punished, but one who consciously commits sinful activities is considered most fallen. Concerning opulence (samrddhi), worn-out, dirty clothing or a messy residence are considered impure for a rich man but acceptable for one who is poor. The word desa indicates that in a safe and peaceful place one is obligated to strictly perform religious rituals, whereas in a dangerous or chaotic situation one may be excused for occasional negligence of secondary principles. One who is physically healthy must offer obeisances to the Deities, attend religious functions and execute his prescribed duties, but a young child or sickly person may be excused from such activities, as indicated by the word avastha. Ultimately, as Srila Rupa Gosvami states:
 
anyabhilasita-sunyam
 jñana-karmady-anavrtam
anukulyena krsnanu-
 silanam bhaktir uttama
 
“One should render transcendental loving service to the Supreme Lord Krsna favorably and without desire for material profit or gain through fruitive activities or philosophical speculation. That is called pure devotional service.” (Bhakti-rasamrta-sindhu 1.1.11) One should accept everything which is favorable for the devotional service of Lord Krsna and reject whatever is unfavorable. One must learn the process of serving God from the bona fide spiritual master and thus always maintain one’s existence pure and free from anxiety. In general, however, when considering the relative purity and impurity of material things, all of the above-mentioned factors must be calculated.
Srimad Bhagavatam Canto 11, Chapter 21, Text 10
Srimad Bhagavatam Canto 11, Chapter 21, Text 12