The shell around the seed has to break before the tree can emerge. You have to get rid of the ego before you gain knowledge.
The sun gets concealed by the clouds. In a like manner, God is concealed by our ego and vasanas (latent tendencies). He becomes visible when the dirt of those tendencies is removed.
The weeds should be removed or the seeds will be destroyed. If we do sadhana (spiritual practices) without eradicating the ego, our sadhana is fruitless.