Short answer. Generally no. Rule 130, Section 24 says the husband or wife, during or after the marriage, cannot be examined without the other's consent about communications received in confidence during the marriage. Two exceptions apply: cases between the spouses themselves, and crimes against the other or their direct ascendants or descendants.
What the law says
The husband or the wife, during or after the marriage, cannot be examined without the consent of the other as to any communication received in confidence by one from the other during the marriage
Rule 130, Section 24 — Disqualification by reason of privileged communication[s]. Read the full provision →
What the law says
except in a civil case by one against the other, or in a criminal case for a crime committed by one against the other or the latter's direct descendants or ascendants
Rule 130, Section 24 — Disqualification by reason of privileged communication[s]. Read the full provision →
What the privilege protects
The clause protects communications received in confidence by one spouse from the other during the marriage. Two boundaries follow from those words. Things a spouse observed rather than was told, and matters that were never confidential in the first place, are not communications received in confidence. And the communication must have occurred during the marriage — confidences exchanged before it began, or after it ended, are outside the clause even though the relationship is the same.
It survives the marriage
The words during or after the marriage matter enormously in practice. A separated or former spouse cannot be examined about what was said in confidence while the marriage subsisted. The privilege attaches to the communication at the moment it was made and does not lapse because the relationship later broke down — which is precisely when the temptation to disclose is strongest. That is the point: a confidence that could be revoked by separation would not be worth much while the marriage lasted.
Whose consent, and the two exceptions
The examination is barred without the consent of the other — the spouse who made the confidence. So it is not for the testifying spouse alone to waive it. The section then carves out two situations: a civil case by one against the other, and a criminal case for a crime committed by one against the other or against that spouse's direct descendants or ascendants. In those cases the privilege would shield the very wrong being litigated, so it gives way.
A different rule from being disqualified as a witness
This clause is about particular confidential communications, not about whether a spouse may testify at all. A spouse may be a perfectly competent witness to facts learned independently while still being barred from repeating what was said in confidence. Keep the two questions separate when the issue arises: what is being asked about, and whether it was a confidence received from the other spouse during the marriage.