"Let the words of my mouth and the meditation of my heart be acceptable in your sight, O Lord, my rock and my redeemer." Psalm 19:14
Reading the Word without meditating on it is like trying to eat without swallowing... pointless, right? Anyone can sit down and read, but it doesn't mean they comprehended it. In school if you read your textbook once it's not likely you will pass the test, but if you take the time to truly study and go over the material then your chances are much higher. The same goes for the Bible. We need to take the time to study and comprehend what we read so we can "pass the test" and help others understand God's amazing grace.
If you don't have time to pray and study the Word, then you are busier than God ever intended you to be. When you mediate, His Word seeks to ensure your heart and it strives to stir you and make you think harder. God wants to work and operate in you so that you will not stray.
Meditating on the Word will make you strong and courageous. It will make you fruitful and give you wisdom and success. It will cause you to see Jesus' glory and live a righteous way of life. Meditation gives you the strength in times of weariness and gives you focus on the love of God.
"I meditate on your precepts and consider Your ways." Psalm 119:13
As you learn to meditate, you will learn to stand firm. Dig your roots deep in faith. Colossians 2:6-7 says, "so then, just as you received Christ Jesus as Lord, continue to live your lives in Him, rooted and built up in Him, strengthened in the faith as you were taught, and overflowing with thankfulness." Endure the winds of time and change as you grow stronger in Him. Be "like a tree firmly planted by streams of living water" (Psalm 1:3) in your faith and relationship with the Lord. As Jeremiah says, "blessed are those who trust in the Lord and have made Him their hope and confidence. They are like trees planted along the water. They are not bothered by the heat or worried by long months of drought." We know that God will take care of us though it all.
So, if you take time to meditate on His word and stay planted like a tree, you will not be shaken.