Siman 111

One must be very careful regarding the juxtaposition of redemption to prayer, meaning that one should not interrupt with anything between "Who redeemed Israel" and the Shemoneh Esrei. Our sages, of blessed memory, said (9b): Anyone who juxtaposes redemption to prayer is not harmed the entire day. And in the Yerushalmi (chapter one, end of halacha 5): Immediately following redemption is prayer, as it is said: "May [the words of my mouth] be acceptable... and my Redeemer"—this is redemption, and juxtaposed to it is: "May Hashem answer you in the day of distress," and this is prayer. And anyone who follows redemption immediately with prayer, the Satan does not prosecute on that day. And anyone who does not juxtapose redemption to prayer, to what is he compared? To a friend of the king who came and knocked on the king's door. The king went out to know what he seeks, and found that he had departed—he too departs, see there.

The Tur wrote: But "amen" after "ga'al Yisrael" is not considered an interruption. Our teacher, the Rema, ruled accordingly. However, our teacher, the Beit Yosef, ruled not to answer "amen" after "ga'al Yisrael." This is also according to the Zohar and so we conduct ourselves, as I have written in siman 66, that one should not answer even Kaddish, Kedushah, and "Barchu" between redemption and prayer. And one waits at "shirah chadashah" as is explained there. The Tur wrote that some are accustomed to say verses beforehand, such as: "O You who hears prayer, to You all flesh shall come," "When I proclaim the name of Hashem, ascribe greatness to our God" – and one should not say them, for it is an interruption. But "Hashem, open my lips, and my mouth shall declare Your praise" – is not an interruption, for since the rabbis instituted it in the prayer – it is considered like a long redemption (Gemara). But in Musaf and Mincha one may say before "Hashem, open my lips" if he wishes, but not afterward.

Our teacher, the Rema, wrote that there are those who say that this requirement to join geulah to tefillah is specifically on a weekday or on a Yom Tov, but on Shabbat it is not necessary. And it is good to be stringent unless there is a need for it. Thus far his words. And the reason for this opinion is that since we derive this from "May the Lord answer you in the day of distress," and Shabbat is not a day of distress. And on Yom Tov it is like a weekday because they are judged on it, as we learned in the first chapter of Rosh Hashanah: On Pesach they are judged for the grain, on Shavuot for the fruit of the tree... But many and great authorities agreed that this verse of "May He answer you" is only a support for this, but joining geulah to tefillah is from the essential law of tefillah. Therefore, it applies also on Shabbat, and such is the custom. And only in Maariv is it more lenient than in Shacharit, and it will be explained in siman 236 with the help of Heaven.

The shaliach tzibbur, when he needs to repeat the prayer aloud, should first say "O Lord, open my lips...". And also at its conclusion, he should say in a whisper "May the words of my mouth...". And even though we do not find a prohibition for a shaliach tzibbur if he interrupts between the silent prayer and the prayer aloud, nevertheless it is proper not to interrupt. And he should not say any verse other than "O Lord, open my lips..." (see Magen Avraham, subsection 4). And if before he has recited Kriat Shema he finds a congregation praying – he should not pray with them, but rather he prays in order so that he may join redemption to prayer, for this is preferable to praying with a congregation. And this is in Shacharit. But in Arvit it is not so, as will be explained in siman 236 with the help of Heaven.