When we read “diligently obey the Lord…” in the Old Testament “obey” is the Hebrew word שָׁמַע (shama) and it means “to hear” (one occurrence is in Zech 6:15).
In Matt 4:4 Jesus repeats Duet 8:23 saying, “Man does not live on bread alone but on every word that comes from the mouth of the Lord.” He used the Greek word ῥῆμα (rhema) which means “spoken word” or “spoken by the Living voice.”
We are to diligently seek “to hear” God’s voice and live everyday at His instruction. There can be no obedience to the Lord if there is not first the “hearing” of His direct voice.
Some may say, “I have a Bible and read His word”… Yes! Always read it and keep reading it BUT the point of the Bible is to lead us into continual deepening relationship with the Lord where we “hear” His voice because we confidently and intimately know Him and from here flows our loving obedience to Him.
Where/when people don’t “hear” His voice they follow religious rules and traditions —the voice of man. Sometimes because they don’t know any different or better. Sometimes because it’s just easier to follow man. Sometimes there is an outright rejection/denial of God’s voice despite the great weight of scripture that makes our “hearing” an imperative. BUT it is the devil who is against the prophetic, living, now-rhema-revelation word of God because he knows without it the church remains crippled and weak, spiritually.
God wants to raise a spiritually strong and vibrant church that gloriously extends His Kingdom. We do this by living everyday waiting on Him and learning to become fully dependent upon His every word.