Must you not then learn to know God, that so you may rightly serve him?

Answer

Yea I must learn to know God ().

Read the 1 proof texts (KJV)

1 Chronicles 28:9: And thou, Solomon my son, know thou the God of thy father, and serve him with a perfect heart and with a willing mind: for the LORD searcheth all hearts, and understandeth all the imaginations of the thoughts: if thou seek him, he will be found of thee; but if thou forsake him, he will cast thee off for ever.