If we thus ask for the guidance and teaching of the Holy Spirit, it will follow, dear friends, that we shall be ready to use all means and helps towards the understanding of the Scriptures.
When Philip asked the Ethiopian eunuch whether he understood the prophecy of Isaiah he replied, “How can I, unless some man should guide me?” Then Philip went up and explained to him the word of the Lord.
From John Piper:
Don’t rest on past reading. Read your Bible more and more every year. Read it whether you feel like reading it or not. And pray without ceasing that the joy return and pleasures increase.
Three reasons this is not legalism:
God only ever wants what is best for those who are in Christ. No matter what the circumstances or how difficult things may seem, he promises it is for our good and his glory.
The Bible offers proof of this. Consider the following passage from Paul's letter to the Romans:
 What then shall we say to these things? If God is for us, who can be against us?  He who did not spare his own Son but gave him up for us all, how will he not also with him graciously give us all things? (ESV)