- Do the Eastern Churches use the same approach to conditional sacraments (mostly regarding baptism)?
I don’t believe so. My understanding is that the Eastern Orthodox have an “all or nothing” approach to it, though they’ll may extend leniency in certain cases with approval.
The Oriental Orthodox are far more nuanced. For example, the Coptic Orthodox do not practice conditional Baptism to my knowledge, but they do recognize Catholic Baptisms as valid. Where it gets confusing is that they
do “re-Baptize” those who come into the Coptic Church
if those people were not Baptized by triple immersion. If you were Baptized by triple immersion, you would be accepted as a Copt without the ritual of triple immersion. Thing is, they don’t view this as a new Baptism per se, but rather as the “filling in the proper form” for Coptic Baptism. The Grace is present regardless, but Copts put a strong emphasis on the symbolism and ritual of triple immersion Baptism, and to be a Copt is to be thrice-immersed. It’s a rather unique perspective and practice, but the closest I can think of for comparison in Latin practice would be having a valid but illicit marriage “blessed” by the Church. It’s not a precise comparison, but I think it suffices to convey the principle, and to indicate that it’s
not a matter of the invalidity of the Sacrament.
The other Oriental Orthodox may have their own practices on the matter.
Peace and God bless!