In taking that fruit he didnot see any impropriety of a sinful nature. One who does not observe purity (in one thing) is expected not to observe it in other things.
दृष्ट्वा फलस्य नापश्यद् दोषान् पापानुबन्धकान्। विविनक्ति न शौचं यः सोऽन्यत्रापि कथं भवेत्॥