Final answer:
Lincoln's statement was an intention to enlist African Americans into federal military service, a move legalized by the Second Confiscation and Militia Act of 1862 and actively pursued after the Emancipation Proclamation in 1863.
Step-by-step explanation:
When Abraham Lincoln stated that "such persons will be received into the armed service of the United States," he was articulating his intentions to formally enlist African Americans into federal military service. This intention was initially legally supported by the Second Confiscation and Militia Act of 1862 and became more practical following the Emancipation Proclamation in January 1863. The involvement of African American troops was seen both as a necessity for the Union war effort and as a strategic advantage to undermine the Confederacy. The Emancipation Proclamation not only declared the freedom of enslaved persons in Confederate states but also sanctioned the recruitment of these individuals as soldiers and sailors, thus enabling them to participate directly in the conflict for their own liberation and the Union cause.