Commentaries:
Verse 13 suggests that Satan had tempted Him much more extensively than what is recorded for us, but He was more than up to the challenge. During those forty days in the wilderness, Jesus was so still that He did not allow even food and water to distract Him from His unity with His Father, who gave Him the strength to endure and overcome the Devil's every test. Preparing for His ministry was so vital that He had to focus entirely on His relationship with God. It took total seclusion from the world to fix His mind on what God wanted Him to do.
The result is that, when He walked out of the wilderness, He came with power and strength to do the difficult, intense work that He knew would end in His sacrificial death to pay for man's sin. That power carried Him forward for a long time, and He frequently recharged it by going to a still place and refocusing on His mission. The product of being still before God is to be filled with spiritual power to do God's will.
Richard T. Ritenbaugh
Beating the Rat Race (Part Six)