If any man have ears to hear, let him hear. And he said unto them, Take heed what ye hear: with what measure ye mete, it shall be measured to you: and unto you that hear shall more be given. (Mark 4:23-24 KJV)
It is not as hard to hear from God as we (believers) make it out to be. God is always speaking to us by His written Word. How we perceive the scriptures can determine how we hear from God. The Word of God is the common denominator of our spirituality. It governs our spiritual walk with God. In order to develop an ear to hear, we must know the Word of God. Understanding the totality and spirit in which the Word of God is expressed will keep you in line with His will.
In this passage of scripture, Christ is telling His audience to pay attention to how they hear. How you respond after hearing the Word of God determines how you heard it. If someone is truly listening with a heart of understanding, then a proper response would follow. After responding the right way to the Word, then more will be given to those that would listen and obey.