The expression suggests that one can begin desiring something by simply looking at it.
وَتُشِيرُ هٰذِهِ ٱلْعِبَارَةُ إِلَى أَنَّ ٱلشَّخْصَ قَدْ يَبْدَأُ بِٱشْتِهَاءِ شَيْءٍ مَا بِمُجَرَّدِ ٱلنَّظَرِ إِلَيْهِ .‏