The Church is coherent with herself when she considers recourse to the infecund periods to be licit, while at the same time condemning, as being always illicit, the use of means directly contrary to fecundation, even if such use is inspired by reasons which may appear honest and serious. In reality, there are essential differences between the two cases; in the former, the married couple make legitimate use of a natural disposition; in the latter, they impede the development of natural processes. It is true that, in the one and the other case, the married couple are concordant in the positive will of avoiding children for plausible reasons, seeking the certainty that offspring will not arrive; but it is also true that only in the former case are they able to renounce the use of marriage in the fecund periods when, for just motives, procreation is not desirable, while making use of it during infecund periods to manifest their affection and to safeguard their mutual fidelity. By so doing, they give proof of a truly and integrally honest love.