# the peace of God

"the peace that God gives"

# which surpasses all understanding

"which is more than we can understand"

# will guard your hearts and your thoughts in Christ

"will be like a soldier and guard your emotions and thoughts in Christ" or "will protect you in Christ and will keep you from worrying about the troubles of this life" 

# your thoughts

The word translated "thoughts" can also be translated "minds," referring to the part of the person that thinks.