Tertullian, On Prayer Chapter 8: The Seventh or Final Clause

For the completeness of so brief a prayer He added—in order that we should supplicate not touching the remitting merely, but touching the entire averting, of acts of guilt—“Lead us not into temptation:” that is, suffer us not to be led into it, by him (of course) who tempts; but far be the thought that the Lord should seem to tempt, as if He either were ignorant of the faith of any, or else were eager to overthrow it. Infirmity and malice are characteristics of the devil. For God had commanded even Abraham to make a sacrifice of his son, for the sake not of tempting, but proving, his faith; in order through him to make an example for that precept of His, whereby He was, by and by, to enjoin that he should hold no pledges of affection dearer than God. He Himself, when tempted by the devil, demonstrated who it is that presides over and is the originator of temptation. This passage He confirms by subsequent ones, saying, “Pray that ye be not tempted;” yet they were tempted, (as they showed) by deserting their Lord, because they had given way rather to sleep than prayer. The final clause, therefore, is consonant, and interprets the sense of “Lead us not into temptation;” for this sense is, “But convey us away from the Evil One.”