In his “Hymn of True Faith,” the Venerable Master wrote:

When doers correctly receive the diamond-like mind,
In accord with the one-thought-moment of joy;
They acquire the “three-fold insight”
And reveal the eternal bliss of dharma-nature
Just as Queen Idaike did.

As expressed here, those with the settled “diamond-like mind” (shinjin) and the resulting joyous mind and heart, acquire the same “three-fold insight” (joy, awakening, confidence).

The Venerable Master Shinran considered acquiring the “three-fold insight” to be the same as entering the “group of those assured (of birth in the Pure Land)” and that doing so guarantees we will be born in the Pure Land where we will attain Enlightenment.

Essentially, what this part of the “Hymn of True Faith” states is that in this present life, those with “settled shinjin” will dwell in the same “group of those assured (of birth in the Pure Land)” that Shakyamuni Buddha taught Queen Idaike in the story of the Tragedy of Osha Castle.

Regarding this point, in the Chapter on Faith of the “Teaching, Practice, Faith and Attainment,” it states that since those with “settled shinjin” are guaranteed to become a Buddha, they are the same as Miryoku Bosatsu. Following this passage, the Venerable Master continued:

Moreover, those who receive the diamond-like mind are the equals of Queen Idaike and realize the insights of joy, awakening, and confidence. This is because they have the true mind directed toward them “(in the aspect of) going (to the Pure Land),” which accords with (the working of) the “mar-velously mysterious” Primal Vow.

In other words, those who receive the shinjin of “Buddhacentered power” receive the same “three-fold insight” of “joy” (ki), “awakening” (go) and “confidence” (shin) that Queen Idaike did, and dwell in the “group of those assured (of birth in the Pure Land).” All this, the Venerable Master Shinran said, is solely due to the power of Amida Buddha’s Primal Vow.

He expressed this in the General Preface to his “Teaching, Practice, Faith and Attainment”: “... Shakya-muni lead (Queen) Idaike to select the Land of Peace and Happiness” after being oppressed by her own son and being jailed, after barely escaping being killed herself. While lamenting her difficulties, Queen Idaike heard and seriously considered Shakyamuni Buddha’s Dharma Talk. As a result, she entered the world of salvation through the Primal Vow, received the “three-fold insight” and entered the “group of those assured (of birth in the Pure Land)” in her present life. This is what the Venerable Master Shinran emphasized and urged us to also become.