In order to the attaining of all useful knowledge this is most necessary, that we fear God; we are not qualified to profit by the instructions that are given us unless our minds be possessed with a holy reverence of God, and every thought within us be brought into obedience to Him.... As all our knowledge must take rise from the fear of God, so it must tend to it as its perfection and centre. Those know enough who know how to fear God, who are careful in every thing to please Him and fearful of offending Him in any thing; this is the Alpha and Omega of knowledge.
Matthew Henry