"All the truth that is necessary for our salvation can be easily understood in a true way by anyone who applies common sense and due diligence in seeking to understand what the Bible teaches."
In contrast to the above and in order to help others who may be confused and/or mislead by such a remarkably obtuse statement:
Meditating on Psalm 119
One of the more remarkable things in this psalm is the number of times the psalmist pleads with God to teach him and instruct him and give him insight and open his eyes that he might understand the Word. The psalmist has no illusions about his own ability to understand God's Word apart from the illumination of its ultimate author. We see this in vv. 12, 18, 19 ("hide not your commandments from me," i.e., disclose them, reveal them to me), 26, 27, 29, 33, 34, 64, 66, 68, 71, 73, 75, 108, 124, 125, 135, 144, 169, 171. If God does not act to unveil and illuminate the meaning of his Word we shall forever remain in darkness. May I suggest, then, that you take these texts and make them your first prayer each time you open God's Word for study or meditation.
There is great significance in the fact that the psalmist also prays that God would do more than teach him what the Law means; he prays that God would "incline" his heart to observe them (see vv. 10, 35, 36, 37, 88, 117, cf. 133). In other words, God is present to incite our souls to obey the insight of our minds! He is committed not simply to illumine our understanding but also to incline our wills. Knowledge that does not lead to action serves only to breed arrogance and pride.
It is only when we understand and embrace the above, that our common sense and due diligence is used to grow us in our understanding as we diligently seek after Him.
Although utterly and in all ways dependent on God for help, don't overlook the fact that the psalmist repeatedly commits himself and "promises" to take action to learn, store up, and diligently keep the Word of God. The antecedent priority of God's work in his heart does not preclude or undermine his responsibility to exercise his will in the active embrace of the Word. We see this, for example, in vv. 8, 11, 15 ("I will delight in your statutes; I will not forget your word"), 30, 32, 44, 57, 59-60, 101-102, 106, 112 ("I incline my heart to perform your statutes forever, to the end"), 145.
The psalmist is also determined to undertake the discipline of meditation. He often speaks of "fixing" his eyes on the commandments of God and laboring "never to forget" them (see vv. 6, 15, 16, 23, 27, 48, 61, 78, 83, 97, 99, 141, 148, 176). This is a healthy and much-needed reminder that God does not operate on us in an intellectual or spiritual vacuum. In other words, if he is going to illumine our minds and incline our wills, his Word must first take root in our hearts.
What blessings and benefits accrue to those who by God's grace and energizing presence actually ingest his Word? What may those expect who fix their faith on obedience to what he has revealed? Here's a sampling: they are declared: "blessed" (vv. 1-2), they "shall not be put to shame" (vv. 6, 31, 46, 80), they will be kept from sinning against God (vv. 9,11), they enjoy beholding wondrous things (v. 18), they are spared scorn and contempt (v. 22), they receive counsel (v. 24), they experience true life (vv. 25, 37, 93), they are strengthened (v. 28), they experience the enlargement of the heart (v. 32), they avoid selfish gain (v. 36), they find wise answers for their enemies (v. 42), they experience comfort and delight in the midst of affliction (vv. 50, 52, 92, 107, 143, 153), as well as "great peace" (165). Wow!
I referred above to the "sin-killing power" of God's Word. What the psalmist had in mind by this was the capacity of God's revealed truth to strengthen us in the face of temptation and to believe his promise of superior joy (cf. Ps. 16:11) when confronted with the passing pleasures of sin. In other words, we find in God's Word the only reliable remedy against the impulses of the flesh and the temptations of the world (see vv. 9, 11, 36, 37, 104, 105). Only when God's ways are sweet to the taste will sin turn sour in our souls.
Excerpts from "Sweeter than Honey to my Mouth!" (Psalm 119)