Zikr means remembrance of God. Zikr is the link to God Almighty. It is not just the repetition of certain words. It means to remember Him again and again in different situations. For example, if you see a tree, you will see the miracle of God in it. You will exclaim, standing with your hand on your heart, “O God! You have made the tree green and fresh, so also, in the same way, make me like a green tree. I am just a dried-up tree. You can turn me into a green tree by your inspiration.” This experience does not relate to any one thing. It relates to all things. Everything in this world contains spiritual food. Wise is the one who can live in this world by taking spiritual food from everything.

Remembering (zikr) is a meaningful reality, not just a turn of phrase. When you remember God, the Lord of the worlds, He will naturally come to your mind as the Owner and Lord of the universe; One whose blessings are so many that they cannot be counted. Contemplation or deep thinking is automatically involved in remembering. That is why zikr means remembering God again and again in different situations. This helps one to live a God-oriented life.

Source: The Spirit of Islam