The Orthodox Church traditionally states that "it blesses the first marriage, performs the second, tolerates the third, and forbids the fourth". Couples who has a divorcee have to get a blessing for a second marriage, and for a third, well... it's short and the clergy are not permitted to attend the reception. If originally married in the Orthodox church, they need to have a ecclesiastical divorce granted before a second or third wedding.
Here is a comparison of part of the prayers the priest says for a first vs second marriage:
Priestly prayer for a first marriage:
Exalt them as the cedars of Lebanon, and as well‑cultured vine; bestow on them a rich store of sustenance, so that having a sufficiency of all things for themselves, they may abound in every good work that is good and acceptable before You. Let them behold their children's children as newly planted olive trees round about their table; and, being accepted before You, let them shine as stars in the Heavens, in You, our Lord, to Whom are due all Glory, honor, and worship as to Your eternal Father, and Your All‑Holy, Good, and Life‑creating Spirit, both now and ever, and to the ages of ages.
Priestly prayer for a second marriage:
O thou who didst forgive Rahab the harlot, and didst accept the repentance of the Publican, remember not our sins of ignorance from our youth up. For if thou shouldest mark iniquity, O Lord, Lord who should stand before thee? Or what flesh should be justified before thee? For thou only art righteous, sinless, holy, plenteous in mercy, of great compassion, and who turnest away from the evils of men. Do thou thyself, O Master, who hast taken unto thyself thy servants N. and N., unite them to one another in love; grant unto them the conversion of the Publican, the tears of the Harlot, and the confession of the Thief, that, through repentance with all their heart, doing thy commandment in peace and oneness of mind, they may be counted worthy of thy heavenly kingdom.
Very very different