“For this people’s heart has grown dull, and with their ears they can barely hear, and their eyes they have closed; lest they should see with their eyes and hear with their ears and understand with their heart and turn, and I would heal them.” Acts 28:27
What a sad verse.
A knife or a saw grows dull over time, with repeated use, and especially after abuse or misuse on unintended tasks (i.e., kitchen knives used to cut wire or rope, not that I know anyone who has ever done that). To remain sharp, the blade needs to be kept honed on a sharpening stone, and used for the purposes for which it was made.
As for a heart toward God, repeated rituals that become meaningless, inattention over time, and engagements in passions foreign to godliness, make dull the awareness of His grace and cool the heat of love for Him to lukewarm. His word still speaks, His arms are still open, yet we fill our ears with man-speak and focus on the urgent so we barely hear and see. Our casual affection and laissez-faire attitude toward Him, while we expend effort, expense, and passion on the temporal and immediate, make for a weak, distracted relationship. What we might excuse as accidental is not–we deliberately choose where to invest our affection and energy, we willfully divert our eyes.
Keep me close, my Whetstone. Heal me of every bit of dull complacency and lethargy toward You. May Your living and active Word, sharper than a two-edged sword, discern my thoughts and actions, pierce my heart, and shape my will, clear my eyes, and attune my ears. (Hebrews 4:12)