The devil said to him, `If you are the Son of God...' Luke 4:3
The first test that our Lord had to face in the wilderness was the temptation to doubt. Satan opened the contest with the insinuation that Christ might be basing his ministry on a false assumption.
Since faith is the vital link between man and God, it is the place where the enemy is most likely to attack. Is our belief and our life work after all based only on an illusion? But to be tempted is not to fall.
Doubts are nourished by the incessant questions `How?' and `Why?'. It is imperative to remember that science cannot prove or disprove spiritual realities. It rightly asks the question `How?'. But the things of the Spirit belong to an altogether different dimension and require a different approach. The victory lies not in the search for intellectually satisfying answers to all problems but in drawing close to God and asking him to speak to us through his word. Our Lord did not argue with the devil, he relied on the authority of scripture.
Doubts that take the form of questioning the wisdom of God's activity or even his existence inevitably disrupt our relationship with him and can lead to arrogant disbelief. On the other hand, a measure of perplexity about certain aspects of Christian truth promotes a spirit of searching and can lead to further understanding and the strengthening of our faith, whereas a glib and purely superficial assertion of certainty may indicate only sterile complacency.
What we do with out doubts is of vital consequence. Faltering faith is most readily strengthened by `looking to Jesus the pioneer and perfecter of our faith' (Heb 12:2). Peter seeing the waves and beginning to sink cried `Lord save me' (Mt 14:30). His security lay in focusing his attention on Jesus rather than on his precarious position.
Further reading: Compare 2 Tim 2:23 and Tit 3:9 with Jn 16:13-14 and Eph 1:15-23).