Quickened means: made alive; revived; vivified; reinvigorated
The psalmist is saying in effect it is your Law, your Holy Word Lord, that makes me live life to the fullest each day. How is this possible only by reading and meditating upon the Word of God daily. Look at verse 92 from the (AMP) below; If Your law had not been my delight, Then I would have perished in my time of trouble. If we do not have God’s Word and the promises it contains to sustain us in times of trouble, how miserable we must be.
I encourage you to read and mediate upon God’s Holy Word daily and quicken your life and walk with our Lord and Savior.
89 Forever, O Lord,
Your word is settled in heaven [standing firm and unchangeable].
90 Your faithfulness continues from generation to generation;
You have established the earth, and it stands [securely].
91 They continue this day according to Your ordinances,
For all things [all parts of the universe] are Your servants.
92 If Your law had not been my delight,
Then I would have perished in my time of trouble.
93 I will never forget Your precepts,
For by them You have revived me and given me life.
94 I am Yours, save me [as Your own];
For I have [diligently] sought Your precepts and required them [as my greatest need].
95 The wicked wait for me to destroy me,
But I will consider Your testimonies.
96 I have seen that all [human] perfection has its limits [no matter how grand and perfect and noble];Your commandment is exceedingly broad and extends without limits [into eternity].