Our Gemara on Amud Beis mentions a concept discussed numerous times in the Gemara and in poskim, aseh docheh lo taaseh, that a positive command in the Torah generally overrides a negative prohibition. For example, a linen four cornered cloak can have wool Tzitizs attached to it, even those this is shaatnez. The sugya in the beginning of Yevamos discusses the sources in depth, but what is the actual meaning behind this order of operations?

On a logical level, prohibitions are more general than commands, because inaction is a more constant state.  Think of it, imagine if it were forbidden to write with a purple marker.  Most often, one is not writing with purple marker, but not in recognition of the prohibition, but rather because being passive is the more constant state.  Yet a mitzvah to write with a purple marker will take focus and intent, and still often you will not be writing.  Thus, the specificity of the positive command does seem to logically override the general negative command. Imagine your doctor tells you that you are quarantined and may not leave the house, but then asks you to come in for some testing. Clearly, the doctor meant do not leave the house, in general, but now for this appointment you need to come in.

Reishis Chokhma (Perek Hamitzvos 2) also uses the idea of aseh docheh lo sa’aseh as a proof to the importance of positive commandments. He says, one might think that since many negative commandments have severe consequences, they are more important than positive commands.  However, we see that a positive command overrides a negative command, therefore it is indeed more important.

Once again, logically we can see why this is true.  Everyone would agree that it is very dangerous to cross the street with your eyes closed, and the consequence is potentially death.  Yet, if I spent my WHOLE day NOT crossing the street, did I accomplish anything? Did I really save my life?  No, of course not. One must do things in order to grow and attain. So too, positive commandments are far superior, despite the terrible consequences of violating a negative commandment.