We are to live, Scripture says, by every word that proceeds from the mouth of God, and that means, of course, from the mouth of the Son of God as well. Many of his words are clear and unquestionable as to their meaning and intent, others somewhat obscure. And sometimes He says one thing at one time and another thing at another time that seems contrary to it. Seems.
One of these pairs of sayings is “He who is not with me is against me” (Mt. ) and “He who is not against us is for us” (Mk. ). The former is quite categorical, uncompromising, and unyielding, while the latter seems rather mild and inclusive. So which is it? The contexts will show us that both are true and apply in the context in which they were spoken.
When the first saying was uttered, Jesus was in a dispute with the Pharisees over the source of his power to cast out demons. Here Jesus was quite stern with them, because they accused Him of using the power of the devil to work miracles. In the battle between good and evil, there must be clear lines drawn, everyone must take a side—no fence-sitters allowed. Either you are on the side of Christ or on that of the devil; there’s no middle ground. Therefore, if you do not choose to side with Christ, you are on the devil’s side by default. Not with Christ? The only alternative is to be against Him, for in the final reckoning there will be only two groups, the “sheep” and the “goats,” the former eternally with Him, the latter irreversibly against Him. Jesus forgives every sin if there is repentance, but what He doesn’t tolerate is calling good evil and evil good, for that is of the devil and it leads the little ones astray.
This saying has many applications today, perhaps most notably in the hotly-contested moral issues of the day. For example, if you are not with Christ and his Church in serious matters involving life (like abortion and euthanasia) or sexual morality (promiscuity, adultery, homosexual activity), then you are by that very fact against Him. Many people do make an obvious show of being against Him, but the more insidious cases are those who say they are with Him, but whose actions, words, and preferences indicate precisely the opposite.
Now what about being for Him and his Church (“us” in the text above) by simply not being against Him? We have a completely different context here, in which the saying is appropriate. The disciples notice someone who was not of their number casting out a demon in Jesus’ name, and they forbade him, “because he was not following us.” Here is Jesus’ reply: “Do not forbid him; for no one who does a mighty work in my name will be able soon after to speak evil of me. For he who is not against us is for us.”
The Pharisees were the ones who “spoke evil” of Jesus, hence placing themselves squarely in the camp of those against Him. Obviously, the man who was casting out demons in Jesus’ name was already for Him, for he recognized his divine authority and placed himself under it, availing himself to be an instrument thereof, even though at that moment he was not among the group of disciples that Jesus originally had chosen. Doing good in Jesus’ name is a safeguard against speaking evil of Him, Jesus explained.
Such a saying can have its application in, say, the ecumenical movement. Not all who do good in Jesus’ name are “following us,” that is, belong to the Catholic Church. But for that reason Jesus would not forbid them to do good in his name. For if they manifest no hostility and do not give other clear evidence that they are in fact against us, we ought to give them the benefit of the doubt that in the divine “economy” they are for us. Perhaps we ought to consider this as we conclude the octave of prayer for Christian unity. All genuine Christians are trying to do good in Jesus’ name, and we ought to try to recognize that, even when we have also to recognize painful and long-standing divisions. We ought also to strive to be for, and not against, each other.
So let us be uncompromising and rock-firm in our commitment to Christ and his Church, in all that pertains to faith and morals, especially in the battle against evil in all its forms. For in this battle if one is not with Him one is surely against Him. But let us also be charitable and accommodating toward those who may be “on the way” but not quite fully integrated in the fold. For if they are not against us, the Holy Spirit will see to it that they are for us.